MedWorm: Intensity-Modulated Radiation Therapy

IMRT versus RapidArc – superiority depends on PTV

MedWire News - Oncology — Mon, 15 Mar 2010 00:00:00 +0100

For men undergoing radiotherapy of the prostate, conventional intensity-modulated radiotherapy performs better than RapidArc in dose sparing of the bladder, rectum, and small bowel for planning target volumes that include the prostate, seminal vesicles, and lymph nodes, researchers report. (Source: MedWire News - Oncology)

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Intensity-modulated radiotherapy outcomes for oropharyngeal squamous cell carcinoma patients stratified by p16 status

Cancer — Thu, 11 Mar 2010 00:00:00 +0100

Patients with oropharyngeal squamous cell carcinoma (OPSCC) treated with intensity-modulated radiotherapy (IMRT) were stratified by p16 status, neck dissection, and chemotherapy to correlate these factors with outcomes.A total of 112 patients with OPSCC treated with IMRT from 2002 to 2008 were retrospectively analyzed. All patients received RT to 66-70 Gray. Forty-five of the tumors were p16 positive (p16+), 27 were p16 negative (p16-), and 41 had unknown p16 status. Sixty-two patients had postradiation neck dissections. Nine patients with p16- tumors and 28 patients with p16+ tumors received chemotherapy. The distribution of T, N, and stage grouping among the p16+ and p16- patients was not significantly different, and 87.5% patients had stage III/IV disease.The median follow-up was 26.3 m...

A novel technique for post-mastectomy breast irradiation utilising non-coplanar intensity-modulated radiation therapy.

The British Journal of Radiology — Thu, 11 Mar 2010 00:00:00 +0100

In conclusion, non-coplanar IMRT results in improved coverage of the PTV and a lower heart dose when compared with a 5F or PWT plan. PMID: 20223909 [PubMed - as supplied by publisher] (Source: The British Journal of Radiology)

A systematic review of trismus induced by cancer therapies in head and neck cancer patients

Supportive Care in Cancer — Wed, 10 Mar 2010 16:02:20 +0100

Conclusions Newer radiation modalities may decrease the prevalence of trismus compared to conventional radiotherapy. Few studies have addressed the quality of life impact of trismus, and no studies were identified to assess the economic impact of trismus. The few preventive and management trials identified in the literature showed some promise, although larger, well-designed studies are required to appropriately assess these therapies before recommendations can be provided. Content Type Journal ArticleCategory Review ArticleDOI 10.1007/s00520-010-0847-4Authors Rene-Jean Bensadoun, CHU de Poitiers Radiotherapy Department, Pôle Régional de Cancérologie 2 rue de la Milétrie, BP 577 86021 Poitiers Cedex 9 FranceDorothea Riesenbeck, Wildermannstr. 21 45659 Recklingh...

IMRT can be faster to deliver than conformal radiotherapy.

Tue, 09 Mar 2010 00:00:00 +0100

Authors: Williams MV, Hoole AC, Dean JC, Russell SG, Thomas SJ, Fairfoul J, Burnet NG PMID: 20223542 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

MHNCS: PET May Predict Cancer Aggression (CME/CE)

MedPage Today Hematology/Oncology — Wed, 03 Mar 2010 19:06:52 +0100

PHOENIX (MedPage Today) -- Pretreatment PET imaging results predicted survival in patients with head and neck squamous cell carcinoma treated with intensity-modulated radiation therapy, a retrospective analysis of data from a clinical series showed. (Source: MedPage Today Hematology/Oncology)

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Adaptive Radiotherapy of Head and Neck Cancer

Seminars in Radiation Oncology — Wed, 03 Mar 2010 13:43:51 +0100

This article reviews the causes and discusses potential solutions to circumvent the discrepancies between the planned dose and the actual dose received by patients treated for H&N malignancies. (Source: Seminars in Radiation Oncology)

Adaptive Radiation Therapy for Prostate Cancer

Seminars in Radiation Oncology — Wed, 03 Mar 2010 13:43:51 +0100

Adaptive radiotherapy has been introduced to manage an individual's treatment by, including patient-specific treatment variation identified and quantified during the course of radiotherapy in the treatment planning and delivering optimization. Early studies have demonstrated that this technique could significantly improve the therapeutic ratio by safely reducing the large target margin that has to be used in conventional radiotherapy for prostate cancer treatment. Clinical application of off-line image-guided adaptive radiotherapy for prostate cancer has demonstrated encouraging clinical outcome. Long-term clinical follow-up has shown significant improvement in terms of tumor control and low toxicity profile, emphasizing the beneficial effect of image-guidance and adaptive treatment. Conti...

Effect of radiation therapy on the latest generation of pacemakers and implantable cardioverter defibrillators: A systematic review

Australasian Radiology — Wed, 03 Mar 2010 00:00:00 +0100

The increasing human lifespan and development of technology over the last number of decades has seen an increase in the number of pacemaker and implantable cardioverter defibrillator (ICD) implantations worldwide. Given the number of risk factors common to both heart disease and cancer, it is not uncommon for several of these patients to present for radiation therapy treatment each year. A systematic review was conducted using online databases Medline and Scopus. Results were grouped into in vitro and in vivo studies. In 1994, the American Association of Physicists in Medicine (AAPM) defined guidelines for the management of these patients, which have since been adopted by many radiation oncology departments internationally. More recently, a number of studies have reported an increase in ra...

Head and neck sarcoma: report of a case treated by intensity-modulated radiation therapy

International Journal of Clinical Oncology — Mon, 01 Mar 2010 18:08:44 +0100

We report on a 71-year-old woman with parapharyngeal sarcoma. Surgery could not be performed because of the size and location of the tumor. After failure of four cycles of chemotherapy, intensity-modulated radiation therapy (IMRT) achieved complete clinical response and partial magnetic resonance imaging response (80%) at 24 months of follow-up. The results of radiotherapy, especially IMRT, for nonresectable head and neck soft tissue sarcoma are discussed. Content Type Journal ArticleCategory Case ReportDOI 10.1007/s10147-010-0037-xAuthors Pierre Heudel, Léon Bérard Cancer Center 28 Rue Laennec 69008 Lyon FranceMarie Claude Biston, Léon Bérard Cancer Center 28 Rue Laennec 69008 Lyon FranceJérome Fayette, Léon Bérard Cancer Center 28 Rue Laennec 69008 Lyon FranceAntoin...

MHNCS: IMRT Effective But Toxic for Recurrent H&N Cancer (CME/CE)

MedPage Today Hematology/Oncology — Mon, 01 Mar 2010 13:43:09 +0100

PHOENIX (MedPage Today) -- Patients with recurrent or second primary squamous-cell head and neck cancer achieved durable tumor control with intensity modulated radiation therapy (IMRT) and chemotherapy, a small retrospective clinical review showed, but the improvement came at a toxic price. (Source: MedPage Today Hematology/Oncology)

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A Feasible Solution to the Beam-Angle-Optimization Problem in Radiotherapy Planning With a DNA-Based Genetic Algorithm

IEEE Transactions on Biomedical Engineering — Mon, 01 Mar 2010 00:00:00 +0100

Intensity-modulated radiotherapy (IMRT) is now becoming a powerful clinical technique to improve the therapeutic radio for cancer treatment. It has been demonstrated that selection of suitable beam angles is quite valuable for most of the treatment plans, especially for the complicated tumor cases and when limited number of beams is used. However, beam-angle optimization (BAO) remains a challenging inverse problem mainly due to the huge computation time. This paper introduced a DNA genetic algorithm (DNA-GA) to solve the BAO problem aiming to improve the optimization efficiency. A feasible mapping was constructed between the universal DNA-GA algorithm and the specified engineering problem of BAO. Specifically, a triplet code was used to represent a beam angle, and the angles of several bea...

Optimizing an analytical dose calculation algorithm for fast 2D calculations.

Zeitschrift fur Medizinische Physik — Mon, 01 Mar 2010 00:00:00 +0100

Authors: Lorenz F, Richter H, Zygmanski P Previously, an analytical dose calculation algorithm for MLC-based radiotherapy was developed and commissioned, which includes a detailed model of various MLC effects as a unique feature [1]. The algorithm was originally developed as an independent verification of the treatment planning system's dose calculation and it explicitly modeled spatial and depth dependent MLC effects such as interleaf transmission, the tongue-and-groove effect, rounded leaf ends, MLC scatter, beam hardening, and divergence of the beam, which in turn resulted in a gradual MLC transmission fall-off with increasing off-axis distance. Originally the algorithm was implemented in Mathematica (Wolfram). To speed up the calculation time and to be able to calculate high resolu...

MHNCS: IMRT Gets High Marks for Oropharyngeal CA (CME/CE)

MedPage Today Hematology/Oncology — Sat, 27 Feb 2010 20:26:34 +0100

PHOENIX (MedPage Today) -- Intensity modulated radiation therapy (IMRT) led to a high rate of long-term local disease control with acceptable acute and late toxicity for patients with oropharyngeal cancer, data from a large retrospective study showed. (Source: MedPage Today Hematology/Oncology)

A systems biology approach to radiation therapy optimization.

Radiation and Environmental Biophysics — Sat, 27 Feb 2010 00:00:00 +0100

Authors: Brahme A, Lind BK During the last 20 years, the field of cellular and not least molecular radiation biology has been developed substantially and can today describe the response of heterogeneous tumors and organized normal tissues to radiation therapy quite well. An increased understanding of the sub-cellular and molecular response is leading to a more general systems biological approach to radiation therapy and treatment optimization. It is interesting that most of the characteristics of the tissue infrastructure, such as the vascular system and the degree of hypoxia, have to be considered to get an accurate description of tumor and normal tissue responses to ionizing radiation. In the limited space available, only a brief description of some of the most important concepts and...

Intensity modulated radiotherapy (IMRT) in benign giant cell tumors - a single institution case series and a short review of the literature

Radiation Oncology — Fri, 26 Feb 2010 00:00:00 +0100

Conclusion: IMRT is a feasible option in giant cells tumors not amendable to complete surgical removal. In our case series local control was achieved in four out of five patients with marked symptom relief in the majority of cases. No severe toxicity was observed. (Source: Radiation Oncology)

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Intensity-modulated radiation therapy (IMRT) vs. 3D conformal radiotherapy (3DCRT) in locally advanced rectal cancer (LARC): dosimetric comparison and clinical implications

Radiation Oncology — Fri, 26 Feb 2010 00:00:00 +0100

Purpose: To compare target dose distribution, comformality, normal tissue avoidance, and irradiated body volume (IBV) in 3DCRT using classic anatomical landmarks (c3DCRT), 3DCRT fitting the PTV (f3DCRT), and intensity-modulated radiation therapy (IMRT) in patients with locally advanced rectal cancer (LARC).Methods and Materials: Fifteen patients with LARC underwent c3DCRT, f3DCRT, and IMRT planning. Target definition followed the recommendations of the ICRU reports No. 50 and 62. OAR (SB and bladder) constraints were D5 50 Gy and Dmax < 55 Gy. PTV dose prescription was defined as PTV95 [greater than or equal to]45 Gy and PTVmin [greater than or equal to] 35 Gy. Target coverage was evaluated with the D95, Dmin, and Dmax. Target dose distribution and comformality was evaluated with the homo...

Carbon ion radiation therapy for high-risk meningiomas.

Thu, 25 Feb 2010 00:00:00 +0100

CONCLUSION: In conclusion, carbon ion radiation shows promising results in patients with atypical or anaplastic meningiomas. Further evaluation in a larger, prospective study in comparison to proton RT or modern photon RT is needed to corroborate these results. PMID: 20189258 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Single Arc Volumetric Modulated Arc Therapy of head and neck cancer.

Wed, 24 Feb 2010 00:00:00 +0100

CONCLUSIONS: The target coverages obtained in the IMRT and VMAT plans were found to be very similar. SmartArc generated single arc VMAT plans with equivalent or better target coverage and sparing of OARs compared to IMRT, while both delivery time and MUs were decreased. Very good dose accuracy results were obtained delivering the plans on an Elekta accelerator. PMID: 20188427 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Vorsprung durch Technik: Evolution, implementation, QA and safety of new technology in radiotherapy

Radiotherapy and Oncology — Mon, 22 Feb 2010 00:00:00 +0100

These are exciting times in radiotherapy. The challenge repeatedly presented to the radiotherapy team by each new patient is one of treatment optimisation i.e., of delivering high and effective doses to the required targets but minimising unwanted side-effects, and this has continued to drive research and the development of technology and techniques. This issue of Radiotherapy and Oncology contains mainly papers from presentations at the recent ESTRO 10th Biennial Conference on Physics and Radiation Technology for Clinical Radiotherapy (Maastricht, September 2009) . Each of these meetings presents the current state of the art and draws together developments over the interval since the last , as also reflected in publications in the journal over that period. Better insights into radiobiolog...

Initial dosimetric evaluation of SmartArc - a novel VMAT treatment planning module implemented in a multi-vendor delivery chain.

Journal of Applied Clinical Medical Physics — Fri, 19 Feb 2010 07:54:03 +0100

Authors: Feygelman V, Zhang GG, Stevens CW We performed an initial dosimetric evaluation of SmartArc - a novel VMAT planning module for Philips Pinnacle treatment planning system. A test suite of structure sets and dose objectives provided by the AAPM for multi-institutional comparison of IMRT dosimetry was used. A total of fifty plans were successfully delivered. The effect of control point spacing on dosimetric accuracy was investigated. When calculated with the 4 masculine spacing, the overall mean point dose errors measured with an ion chamber were 0.5+/-1.4 and -0.3+/-1.4% for the PTV and OAR, respectively. The gamma(3%,3mm) passing rate, measured for absolute dose with a biplanar diode array, was 98.2+/-1.6% (range 94.5-99.9%). Ninety percent of the passing rate values were above...

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Angular dose dependence of Matrixx TM and its calibration.

Journal of Applied Clinical Medical Physics — Fri, 19 Feb 2010 07:54:03 +0100

In this study, the angular dependence of MatrixxEvolution has been characterized and a method for its calibration was developed. Relatively large discrepancies were found in dose response for anterior vs. posterior fields for four different MatrixxEvolution detectors (up to 11%). And relatively large variability of responses as a function of gantry angle, specifically in angle ranges of 91 degrees -110 degrees and 269 degrees -260 degrees . With our calibration method, the bias due to angular dependence is effectively removed in experimental verification of IMRT and VMAT plans. PMID: 20160692 [PubMed - in process] (Source: Journal of Applied Clinical Medical Physics)

Helical Tomotherapy in the radiotherapy treatment of Hodgkin's disease- a feasibility study.

Journal of Applied Clinical Medical Physics — Fri, 19 Feb 2010 07:54:03 +0100

Authors: Vlachaki MT, Kumar S Radiation therapy for advanced Hodgkin's disease often requires large fields and may result in significant exposure of normal tissues to ionizing radiation. In long-term survivors, this may increase the risk for late toxicity including secondary malignancies. 3DCRT has been successfully used to treat this disease but treatment delivery is often complex requiring matching of photon with electron beams, utilization of field-in-field techniques and of partial transmission blocks. HT is an arc-rotational intensity modulated radiation therapy technique proven to achieve superior target dose conformality and sharp dose gradients around critical normal tissues. HT however, has also been associated with higher volumes of low dose regions in normal tissues and ther...

A computational tool for the efficient analysis of dose-volume histograms from radiation therapy treatment plans.

Journal of Applied Clinical Medical Physics — Fri, 19 Feb 2010 07:54:03 +0100

Authors: Pyakuryal A, Myint WK, Gopalakrishnan M, Jang S, Logemann JA, Mittal BB A Histogram Analysis in Radiation Therapy (HART) program was developed to increase the efficiency and accuracy of dose-volume histogram (DVH) analysis for radiation therapy research. HART was written in MATLAB to analyze patient plans exported from the treatment planning system (Pinnacle3) in the American Association of Physicists in Medicine/Radiation Therapy Oncology Group (AAPM/RTOG) format. DVH data were converted from differential histograms to cumulative histograms and compared with those manually extracted from the planning system for five patients treated with the IMRT technique. HART calculated over 4000 parameters from the differential DVH curves for each patient in approximately 10-15 minutes. M...

Extension of the NCAT phantom for the investigation of intra-fraction respiratory motion in IMRT using 4D Monte Carlo.

Physics in Medicine and Biology — Fri, 19 Feb 2010 07:36:08 +0100

Authors: McGurk R, Seco J, Riboldi M, Wolfgang J, Segars P, Paganetti H The purpose of this work was to create a computational platform for studying motion in intensity modulated radiotherapy (IMRT). Specifically, the non-uniform rational B-spline (NURB) cardiac and torso (NCAT) phantom was modified for use in a four-dimensional Monte Carlo (4D-MC) simulation system to investigate the effect of respiratory-induced intra-fraction organ motion on IMRT dose distributions as a function of diaphragm motion, lesion size and lung density. Treatment plans for four clinical scenarios were designed: diaphragm peak-to-peak amplitude of 1 cm and 3 cm, and two lesion sizes-2 cm and 4 cm diameter placed in the lower lobe of the right lung. Lung density was changed for each phase using a conservation...

Urology Study Shows Reduced Side Effects From Radiation For Prostate Cancer With Calypso Medical's Tumor Tracking Technology

Health News from Medical News Today — Thu, 18 Feb 2010 08:00:00 +0100

Calypso Medical Technologies, Inc., a developer of targeting technology used for accurate, precise real-time tracking of tumor targets, announced the online publication of a clinical study in Urology (The GOLD JOURNAL). The prospective, multi-site study, entitled, "Assessing the Impact of Margin Reduction (AIM)," is the first outcomes-based study to evaluate the quality of life of high-dose intensity-modulated radiotherapy (IMRT) to the prostate with tightly contoured treatment technically described as "reduced treatment margins... (Source: Health News from Medical News Today)

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Limited benefit of inversely optimised intensity modulation in breast conserving radiotherapy with simultaneously integrated boost.

Thu, 18 Feb 2010 00:00:00 +0100

CONCLUSIONS: In breast-conserving RT, results obtained with 3D-CRT-SIB and IMRT-SIB are generally comparable. Patient characteristics could be used to identify patients that are most likely to benefit from IMRT-SIB. PMID: 20171751 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

IMRT-based optimization approaches for volumetric modulated single arc radiotherapy planning.

Thu, 18 Feb 2010 00:00:00 +0100

This study includes 11 patients with adenocarcinoma of the prostate. Rectal Normal Tissue Complication Probability is used as a constraint in a dose escalation. RapidArc(R) rectal NTCP's are lower than those of IMRT (p=0.007). This allows a mean dose escalation of 2.1Gy([0.7Gy,3.5Gy]). PMID: 20171750 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Urology Study Shows Reduced Side Effects from Radiation for Prostate Cancer with Calypso Medical's Tumor Tracking Technology

HSMN NewsFeed — Tue, 16 Feb 2010 18:39:28 +0100

Calypsos accurate, real-time tumor tracking allows for high doses with tightly contoured treatment, while reducing side effects and toxicity to surrounding healthy tissue SEATTLE--(HSMN NewsFeed)--Calypso Medical Technologies, Inc., a developer of targ... Devices, Oncology, UrologyCalypso Medical Technologies, radiotherapy, IMRT, prostate cancer (Source: HSMN NewsFeed)

Study: IMRT bests conventional therapy for prostate cancer

Health Imaging News — Tue, 16 Feb 2010 16:25:34 +0100

Highly contoured intensity-modulated radiotherapy (IMRT) may be a successful strategy for reducing morbidity in prostate cancer treatment, as patients involved were found to have less radiotherapy related morbidity than their counterparts treated with conventional target volume margins, based on study findings published online Feb. 16 in Urology. (Source: Health Imaging News)

Study: IMRT bests conventional therapy for prostate cancer

Health Imaging News — Tue, 16 Feb 2010 16:25:34 +0100

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Proton-Beam, Intensity-Modulated, and/or Intraoperative Electron Radiation Therapy Combined with Aggressive Anterior Surgical Resection for Retroperitoneal Sarcomas

Annals of Surgical Oncology — Fri, 12 Feb 2010 07:20:47 +0100

Conclusions Aggressive resection of retroperitoneal sarcomas can achieve a disease-negative anterior margin. PBRT and/or IMRT with IOERT may possibly deliver sufficient radiation dose to the posterior margin to control microscopic residual disease. This strategy may minimize radiation-related morbidity and reduce local recurrence, especially in patients with primary disease. Content Type Journal ArticleCategory Bone and Soft Tissue SarcomasDOI 10.1245/s10434-010-0935-1Authors Sam S. Yoon, Massachusetts General Hospital, and Harvard Medical School Division of Surgical Oncology, Department of Surgery Boston MA USAYen-Lin Chen, Massachusetts General Hospital, and Harvard Medical School Department of Radiation Oncology Boston MA USADavid G. Kirsch, Duke University Medical...

Maintenance of Sorafenib following combined therapy of three-dimensional conformal radiation therapy/intensity-modulated radiation therapy and transcatheter arterial chemoembolization in patients with locally advanced hepatocellular carcinoma: a phase I/II study

Radiation Oncology — Fri, 12 Feb 2010 00:00:00 +0100

In this study, local therapy for HCC is the combination of TACE and radiotherapy. Radiation exposure as a kind of stress might induce the compensatory activations of multiple intracellular signaling pathway mediators, such as PI3K, MAPK, JNK and NF-kB. Vascular endothelial growth factor (VEGF) was identified as one factor that was increased in a time- and dose-dependent manner after sublethal irradiation of HCC cells in vitro, translating to enhanced intratumor angiogenesis in vivo. Therefore, Sorafenib-mediated blockade of the Raf/MAPK and VEGFR pathways might enhance the efficacy of radiation, when Sorafenib is followed sequentially as a maintenance modality. (ClinicalTrials.gov number, NCT00999843.) (Source: Radiation Oncology)

Dose escalation in image-guided, intensity-modulated radiotherapy of carcinoma prostate: Initial experience in India

Journal of Cancer Research and Therapeutics — Thu, 11 Feb 2010 13:47:35 +0100

Conclusions</b> : IGRT technique using MVCBCT for implanted fiducial gold seed localization was feasible for IMRT dose escalation in carcinoma prostate with excellent results. (Source: Journal of Cancer Research and Therapeutics)

Sequential chemotherapy and intensity-modulated radiation therapy in the management of locoregionally advanced nasopharyngeal carcinoma: Experience of 370 consecutive cases

BMC Cancer — Wed, 10 Feb 2010 00:00:00 +0100

Purpose: To investigate the outcome of locoregionally advanced nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) after induction chemotherapy, with or without concomitant chemotherapy. Methods: Between August 2003 and March 2007, 370 patients with locoregionally advanced NPC were treated with IMRT. Presenting stages were stage IIB in 62, stage III in 197, and stage IVA/B in 111 patients. All patients except for 36 patients with cervical lymphadenopathy of 4 cm or less in diameter received 2 cycles of cisplatin-based neoadjuvant chemotherapy. Forty-eight patients received cisplatin-based concurrent chemotherapy as well. Results: With a median follow-up time of 31 months (range 5 to 61 months), the 3-year local control, regional control, metastasis-fre...

Misses and near-misses after postoperative radiation therapy for head and neck cancer: Comparison of IMRT and non-IMRT techniques in the CT-simulation era

Head and Neck — Tue, 09 Feb 2010 00:00:00 +0100

The purpose of this study was to compare the patterns of failure focusing on the distribution of local-regional recurrence among patients treated postoperatively with conventional radiotherapy (RT) and intensity-modulated radiotherapy (IMRT) for head and neck cancer.The records of 130 patients treated by surgery and postoperative radiation therapy for squamous cell carcinoma of the head and neck were reviewed. Seventy-eight patients (60%) were treated using conventional RT and 52 patients (40%) were treated using IMRT.The 3-year estimates of local-regional control were 70% and 73% among patients treated by conventional RT and IMRT, respectively (p = .33). Among the local-regional recurrences in the IMRT group, 9 were in-field recurrences occurring within the physician-designated clinical t...

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American Society for Radiation Oncology Announces Patient Protection Plan

NABTC — Sun, 07 Feb 2010 18:01:59 +0100

The American Society for Radiation Oncology (ASTRO) announced a six-point patient protection on February 3, 2010. The plan was described as the culmination of a long-term effort to assure that patients receive safe and effective radiation therapy, an effort that continued at the ASTRO Board of Directors winter meeting on January 28-31, 2010. The ASTRO plan includes the following recommendations: 1) creating a database for the reporting of linear accelerator- and computed tomography-based medical errors, 2) launching an enhanced practice accreditation program, specifically addressing new, advanced technologies such as IMRT, SBRT, and brachytherapy, 3) expanding educational programs, with special emphasis on quality assurance and safety, 4) working with patient support organizations to dev...

IMRT for the breast: a comparison of tangential planning techniques.

Physics in Medicine and Biology — Sat, 06 Feb 2010 05:46:20 +0100

Authors: Smith W, Menon G, Wolfe N, Ploquin N, Trotter T, Pudney D Three intensity-modulated tangential beam radiotherapy plan types for breast cancer treatment were evaluated based on PTV homogeneity index (HI) and equivalent uniform dose (EUD), heart V30 and EUD, whole lung V20 and EUD, and typical planning time compared to conventional 2D plans. 20 early-stage breast cancer patients were CT-scanned in the supine position, and tangential field extent, gantry and collimator angles were chosen. Four treatment plans were created for each patient: conventional, dynamically wedged plan based on the dose distribution on the central axial slice; forward planned IMRT; surface compensated plan created using an Eclipse tool and hybrid IMRT plan combining open and inverse-optimized fields. All ...

Clinical performance of a transmission detector array for the permanent supervision of IMRT deliveries.

Thu, 04 Feb 2010 00:00:00 +0100

CONCLUSIONS: The DAVID system permits the on-line detection of clinically relevant MLC discrepancies in IMRT deliveries. PMID: 20138379 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Addenbrooke's Hospital Begins Treating Patients on Second TomoTherapy(R) Cancer Treatment System

HSMN NewsFeed — Tue, 02 Feb 2010 16:07:18 +0100

Expanded Capacity Provides Cambridge, England-Based Hospital With Ability to Treat More Patients With Advanced Image-Guided IMRT MADISON, WI - (HSMN NewsFeed) - TomoTherapy Incorporated (NASDAQ:TOMO ), maker of advanced radiation therapy solutions for c... Devices, OncologyTomoTherapy, Hi-Art, radiotherapy, IMRT (Source: HSMN NewsFeed)

How To Prevent Radiation Mistakes In Cancer Patients

Health News from Medical News Today — Tue, 02 Feb 2010 09:00:00 +0100

Recent media stories have reported isolated cases of cancer patients who were injured by incorrect doses from intensity-modulated radiation therapy (IMRT). Despite such reports, IMRT remains one the most powerful cancer treatments, and extensive safety measures can ensure patients receive the proper doses, said radiation oncologist Dr. Kevin Albuquerque of Loyola University Health System. IMRT uses computer-controlled linear accelerators to deliver precise radiation doses to a tumor or areas within a tumor... (Source: Health News from Medical News Today)

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How To Prevent Radiation Mistakes In Cancer Patients

Cancer / Oncology News From Medical News Today — Tue, 02 Feb 2010 09:00:00 +0100

Recent media stories have reported isolated cases of cancer patients who were injured by incorrect doses from intensity-modulated radiation therapy (IMRT). Despite such reports, IMRT remains one the most powerful cancer treatments, and extensive safety measures can ensure patients receive the proper doses, said radiation oncologist Dr. Kevin Albuquerque of Loyola University Health System... (Source: Cancer / Oncology News From Medical News Today)

A two-variable linear model of parotid shrinkage during IMRT for head and neck cancer

Radiotherapy and Oncology — Mon, 01 Feb 2010 00:00:00 +0100

Conclusions: IPV/age and Dmean/V40 are the major dosimetric and clinical/anatomic predictors of ΔVcc and ΔV%. ΔVcc and ΔV% may be well described by bi-linear models including the above-mentioned variables. (Source: Radiotherapy and Oncology)

Volumetric modulated arc therapy versus conventional intensity modulated radiation therapy for stereotactic spine radiotherapy: A planning study and early clinical data

Radiotherapy and Oncology — Mon, 01 Feb 2010 00:00:00 +0100

Conclusions: Both RA and conventional IMRT plans deliver high quality vertebral SBRT, but plan quality was poorer when the PTV consisted of the entire vertebra. (Source: Radiotherapy and Oncology)

Volumetric modulated arc therapy versus conventional intensity modulated radiation therapy for stereotactic spine radiotherapy: A planning study and early clinical data.

Sat, 30 Jan 2010 00:00:00 +0100

CONCLUSIONS: Both RA and conventional IMRT plans deliver high quality vertebral SBRT, but plan quality was poorer when the PTV consisted of the entire vertebra. PMID: 20122745 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

A Two-step Intensity-modulated Radiation Therapy Method for Nasopharyngeal Cancer: The Kinki University Experience

Japanese Journal of Clinical Oncology — Fri, 29 Jan 2010 11:44:41 +0100

Conclusions Excellent overall survival and loco-regional control rates were obtained by a two-step IMRT method with concurrent chemotherapy for NPC, although marginal recurrence was noted in some early cases. (Source: Japanese Journal of Clinical Oncology)

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Phase I dose-finding study of paclitaxel with panitumumab, carboplatin and intensity-modulated radiotherapy in patients with locally advanced squamous cell cancer of the head and neck

Annals of Oncology — Fri, 29 Jan 2010 00:07:10 +0100

Conclusions: Panitumumab, carboplatin, paclitaxel and IMRT are well tolerated and appear highly active in the treatment of SCCHN. Further study of this regimen in SCCHN is warranted. (Source: Annals of Oncology)

A two-variable linear model of parotid shrinkage during IMRT for head and neck cancer.

Fri, 29 Jan 2010 00:00:00 +0100

CONCLUSIONS: IPV/age and Dmean/V40 are the major dosimetric and clinical/anatomic predictors of DeltaVcc and DeltaV%. DeltaVcc and DeltaV% may be well described by bi-linear models including the above-mentioned variables. PMID: 20117852 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Comparison of electron IMRT to helical photon IMRT and conventional photon irradiation for treatment of breast and chest wall tumours.

Wed, 27 Jan 2010 00:00:00 +0100

CONCLUSIONS: Electron IMRT is superior to conventional irradiation, as it allows satisfying target coverage and avoids high doses in underlying organs. Its advantage over photon IMRT is better sparing of most organs at risk (low-dose effects) which reduces the risk of radiation-induced malignancies. PMID: 20116121 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Current technological clinical practise in breast radiotherapy; results of a survey in EORTC-Radiation Oncology Group affiliated institutions.

Wed, 27 Jan 2010 00:00:00 +0100

CONCLUSIONS: This survey provides insight in the current practise of radiation technology used in the treatment of breast cancer among institutions participating in EORTC-ROG clinical trials. PMID: 20116120 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Varian Medical Systems Accredits Royal North Shore Hospital As Australia's First Image-Guided Radiotherapy School

Health News from Medical News Today — Tue, 26 Jan 2010 14:00:00 +0100

The Radiation Oncology Department at Royal North Shore Hospital in Sydney has become the first in Australia to be formally accredited by Varian Medical Systems (NYSE: VAR), the world leader in radiotherapy, as a teaching facility for image-guided radiotherapy (IGRT). The hospital will hold four IGRT courses in 2010 and there are plans to extend this accreditation to other advanced techniques such as intensity-modulated radiotherapy (IMRT) and RapidArc® in the future... (Source: Health News from Medical News Today)

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Postmastectomy intensity modulated radiation therapy following immediate expander-implant reconstruction.

Thu, 21 Jan 2010 00:00:00 +0100

CONCLUSIONS: In women undergoing immediate expander-implant reconstruction, PMRT can achieve excellent local control with acceptable heart and lung doses. These results can be achieved even when the IMN are being treated, although doses to the heart and lungs will be higher. PMID: 20096946 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Esophageal motion during radiotherapy: quantification and margin implications

Diseases of the Esophagus — Wed, 20 Jan 2010 00:00:00 +0100

The purpose was to evaluate interfraction and intrafraction esophageal motion in the right[ndash]left (RL) and anterior[ndash]posterior (AP) directions using computed tomography (CT) in esophageal cancer patients. Eight patients underwent CT simulation and CT-on-rails imaging before and after radiotherapy. Interfraction displacement was defined as differences between pretreatment and simulation images. Intrafraction displacement was defined as differences between pretreatment and posttreatment images. Images were fused using bone registries, adjusted to the carina. The mean, average of the absolute, and range of esophageal motion were calculated in the RL and AP directions, above and below the carina. Thirty-one CT image sets were obtained. The incidence of esophageal interfraction motion ...

Adenocarcinoma of the paranasal sinuses and nasal cavity with lung metastasis showing complete response to combination chemotherapy with docetaxel, cisplatin and 5-fluorouracil (TPF): A case report

Auris, Nasus, Larynx — Tue, 19 Jan 2010 14:18:37 +0100

We report the case of a 62-year-old man who presented with nasal congestion and epistaxis. We were unable to observe an oncogenic lesion in the nasal cavity directly, but the tumor gave inhomogeneous low intensity signals on T1-weighted images and an isointense signal on T2-weighted images in MRI. Adenocarcinoma was diagnosed by open biopsy. Six courses of chemotherapy by super-selective intra-arterial infusion of cisplatin with concurrent intensity-modulated radiation therapy of 70Gy were performed at another hospital. However, the tumor enlarged and developed distant metastasis to the lung after this therapy. Therefore, TPF chemotherapy (docetaxel, cisplatin and 5-fluorouracil) was performed 5 times, after which the tumor gradually reduced in size. The patient is alive after a follow-up ...

Minimising contralateral breast dose in post-mastectomy intensity-modulated radiotherapy by incorporating conformal electron irradiation

Radiotherapy and Oncology — Mon, 18 Jan 2010 00:00:00 +0100

Conclusions: Incorporation of conformal electron irradiation in post-mastectomy IMRTp/e enables a heart dose reduction which can only be obtained with IMRTp when allowing large irradiated volumes in the contralateral breast. (Source: Radiotherapy and Oncology)

Determining DVH parameters for combined external beam and brachytherapy treatment: 3D biological dose adding for patients with cervical cancer

Radiotherapy and Oncology — Mon, 18 Jan 2010 00:00:00 +0100

Conclusion: Without an EBRT boost ‘parameter adding’, as proposed by the GEC-ESTRO, yielded accurate results for the values for DVH parameters. If an EBRT boost is given ‘distributions adding’ should be considered. (Source: Radiotherapy and Oncology)

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A two-stage sequential linear programming approach to IMRT dose optimization.

Physics in Medicine and Biology — Sat, 16 Jan 2010 17:12:30 +0100

Authors: Zhang HH, Meyer RR, Wu J, Naqvi SA, Shi L, D'Souza WD The conventional IMRT planning process involves two stages in which the first stage consists of fast but approximate idealized pencil beam dose calculations and dose optimization and the second stage consists of discretization of the intensity maps followed by intensity map segmentation and a more accurate final dose calculation corresponding to physical beam apertures. Consequently, there can be differences between the presumed dose distribution corresponding to pencil beam calculations and optimization and a more accurately computed dose distribution corresponding to beam segments that takes into account collimator-specific effects. IMRT optimization is computationally expensive and has therefore led to the use of heurist...

A basic dosimetric study of PRESAGE: the effect of different amounts of fabricating components on the sensitivity and stability of the dosimeter.

Physics in Medicine and Biology — Sat, 16 Jan 2010 17:12:11 +0100

This study has focused on the assessment of dosimetric characteristics of PRESAGE for various amounts of components in its formulation. To achieve this, PRESAGE dosimeters were fabricated using various amounts of their constituting components. Then the dosimeters were irradiated to (60)Co gamma photons for a range of radiation doses from 0 to 50 Gy. Consequently, the light absorption changes of the dosimeters were measured by a spectrophotometer at different post-irradiation time periods. It was generally observed that as the concentration of the radical initiator is increased, the PRESAGE dosimeter sensitivity is increased while its stability is decreased. Furthermore, it was noted that with the high concentration of the radical initiator and leuco dye, the sensitivity of PRESAGE is decre...

Minimising contralateral breast dose in post-mastectomy intensity-modulated radiotherapy by incorporating conformal electron irradiation.

Fri, 15 Jan 2010 00:00:00 +0100

CONCLUSIONS: Incorporation of conformal electron irradiation in post-mastectomy IMRT(p/e) enables a heart dose reduction which can only be obtained with IMRT(p) when allowing large irradiated volumes in the contralateral breast. PMID: 20080312 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Determining DVH parameters for combined external beam and brachytherapy treatment: 3D biological dose adding for patients with cervical cancer.

Fri, 15 Jan 2010 00:00:00 +0100

CONCLUSION: Without an EBRT boost 'parameter adding', as proposed by the GEC-ESTRO, yielded accurate results for the values for DVH parameters. If an EBRT boost is given 'distributions adding' should be considered. PMID: 20080309 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

In Regards to Dr. Eisbruch A et al. (Int J Radiat Oncol Biol Phys 2009. Electronic Publication, June 17, 2009.)

International Journal of Radiation Oncology * Biology * Physics — Wed, 13 Jan 2010 15:20:42 +0100

To the Editor: Eisbruch et al. recently published the results of a Radiation Therapy Oncology Group (RTOG) trial of oropharyngeal cancer. This was a significant study for a number of reasons, among them that this was the first use of intensity-modulated radiation therapy (IMRT) in a prospective multi-institutional trial and also that it was the first trial to require participants to undergo IMRT credentialing tests before registering patients. (Source: International Journal of Radiation Oncology * Biology * Physics)

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ASTRO News

International Journal of Radiation Oncology * Biology * Physics — Wed, 13 Jan 2010 15:20:42 +0100

The Current State of the Art Techniques for IMRT, IGRT and SBRT symposium is scheduled for May 14-16, 2010, at the Fairmont hotel in Dallas. Attendees will receive the latest information on techniques used in the adaptation of IMRT, IGRT and SBRT that the successful clinician needs to review and decide on criteria, such as patient selection, immobilization options, setup uncertainties, multimodality imaging, image registration, motion evaluation and management, quality assurance, and correction strategies. For registration and housing information visit http://www.astro.org/Meetings/UpcomingMeetings/IGRTSymposium. (Source: International Journal of Radiation Oncology * Biology * Physics)

Comments on 'The influence of a novel transmission detector on 6 MV x-ray beam characteristics'

Medical Physics — Thu, 07 Jan 2010 00:00:00 +0100

Authors: Harder D In their recent paper (Venkataraman et al 2009 Phys. Med. Biol. 54 3173-83) the authors reported on photon beam attenuation and secondary electron production in the novel transmission detector COMPASS, to be placed in the accessory holder of the linac treatment head. In the interest of IMRT patient safety, space-resolved measurements by transmission detectors analysing the MLC-shaped photon fluence pattern in real time are in fact an urgent item for equipment designers. However, there are some constraints for the construction of such devices. The COMPASS system, at its present stage of development, has difficulties in complying with the constraints that the spatial sampling rate should fit the desired task and that the enhanced secondary electron contamination of the ...

Cone-Beam CT Assessment of Interfraction and Intrafraction Setup Error of Two Head-and-Neck Cancer Thermoplastic Masks

International Journal of Radiation Oncology * Biology * Physics — Thu, 07 Jan 2010 00:00:00 +0100

Conclusions: Interfraction and intrafraction setup error is not significantly different for SSMs and conventional masks in head-and-neck radiation therapy. Mask cutouts should be considered for these patients in an effort to reduce skin toxicity. (Source: International Journal of Radiation Oncology * Biology * Physics)

Dose recalculation in megavoltage cone-beam CT for treatment evaluation: Removal of cupping and truncation artefacts in scans of the thorax and abdomen.

Wed, 06 Jan 2010 00:00:00 +0100

CONCLUSIONS: The method corrects cupping and truncation artefacts in cone-beam scans of the thorax and abdomen in addition to head-and-neck (demonstrated previously). The corrected scans can be used to calculate the influence of anatomical changes on the 3D-delivered dose distribution. PMID: 20060186 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Dosimetric impact of daily setup variations during treatment of canine nasal tumors using intensity-modulated radiation therapy

Veterinary Radiology & Ultrasound — Mon, 04 Jan 2010 00:00:00 +0100

This study provides a detailed analysis of the impact of daily setup variations on optimized IMRT canine nasal tumor treatment plans when variations are not accounted for due to the lack of image guidance. Setup histories of ten patients with nasal tumors previously treated using helical tomotherapy were replanned retrospectively to study the impact of daily setup variations on IMRT dose distributions. Daily setup shifts were applied to IMRT plans on a fraction-by-fraction basis. Using mattress immobilization and laser alignment, mean setup error magnitude in any single dimension was at least 2.5 mm (0[ndash]10.0 mm). With inclusions of all three translational coordinates, mean composite offset vector was 5.9±3.3 mm. Due to variations, a loss of equivalent uniform dose for target volumes ...

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Toxicity risk of non-target organs at risk receiving low-dose radiation: case report

Radiation Oncology — Thu, 31 Dec 2009 00:00:00 +0100

The spine is the most common site for bone metastases. Radiation therapy is a common treatment for palliation of pain and for prevention or treatment of spinal cord compression. Helical tomotherapy (HT), a new image-guided intensity modulated radiotherapy (IMRT), delivers highly conformal dose distributions and provides an impressive ability to spare adjacent organs at risk, thus increasing the local control of spinal column metastases and decreasing the potential risk of critical organs under treatment. However, there are a lot of non-target organs at risk (OARs) occupied by low dose with underestimate in this modern rotational IMRT treatment. Herein, we report a case of a pathologic compression fracture of the T9 vertebra in a 55-year-old patient with cholangiocarcinoma. The patient unde...

Radiotherapy Treatment Plans With RapidArc for Prostate Cancer Involving Seminal Vesicles and Lymph Nodes

International Journal of Radiation Oncology * Biology * Physics — Wed, 30 Dec 2009 00:00:00 +0100

Conclusion: For PTVs including prostate, seminal vesicles, and lymph nodes, IMRT performed better in dose sparing for bladder, rectum, and small bowel than did RapidArc. For PTVs including prostate and seminal vesicles, RapidArc with two arcs provided plans comparable to those for IMRT. The treatment delivery is more efficient with RapidArc. (Source: International Journal of Radiation Oncology * Biology * Physics)

Travel Grants for Current State of the Art Techniques for Intensity Modulated Radiation Therapy, Image Guided Radiation Therapy and Stereotactic Body Radiotherapy Symposium

ScanGrants feed — Tue, 29 Dec 2009 00:00:00 +0100

Current State of the Art Techniques for IMRT, IGRT and SBRT SymposiumThe Fairmont DallasMay 14-16, 2010 Program OverviewThe Current State of the Art Techniques for IMRT, IGRT and SBRT Symposium is a two-and-a-half-day meeting focusing on disease site specific radiation therapy treatment from planning to delivery. It will be presented through didactic lectures, panels, breakout sessions and interactive sessions.At least 60 percent of cancer patients receive radiation therapy as part of their treatment. The latest advances in imaging and computer technology have revolutionized how radiation therapy is delivered to these patients. Intensity modulated radiation therapy (IMRT), image guided radiation therapy (IGRT) and stereotactic body radiotherapy (SBRT) represent three high-precision techno...

Standard chemoradiation versus intensity-modulated chemoradiation: a quality of life assessment in oropharyngeal cancer patients

European Archives of Oto-Rhino-Laryngology — Mon, 28 Dec 2009 19:13:52 +0100

In conclusion, CIMRT results in improved QOL for some domains but surprisingly not for swallowing or saliva. Patients undergoing CIMRT also report slightly better QOL overall when compared to patients receiving more traditional forms of radiation therapy. Content Type Journal ArticleCategory Head and NeckDOI 10.1007/s00405-009-1183-5Authors Sarah E. Mowry, University of California, Los Angeles Division of Head and Neck Surgery, David Geffen School of Medicine 62-132 CHS BOX 951624 Los Angeles CA 90095-1624 USAChristopher Tang, University of California, Los Angeles Division of Head and Neck Surgery, David Geffen School of Medicine 62-132 CHS BOX 951624 Los Angeles CA 90095-1624 USAAhmad Sadeghi, VA Greater Los Angeles Healthcare System Department of Radiation Oncology Los Angeles USA...

Hybrid plan verification for intensity-modulated radiation therapy (IMRT) using the 2D ionization chamber array I'mRT MatriXX--a feasibility study.

Physics in Medicine and Biology — Wed, 23 Dec 2009 14:14:18 +0100

Authors: Dobler B, Streck N, Klein E, Loeschel R, Haertl P, Koelbl O The 2D ionization chamber array I'mRT MatriXX (IBA, Schwarzenbruck, Germany) has been developed for absolute 2D dosimetry and verification of intensity-modulated radiation therapy (IMRT) for perpendicular beam incidence. The aim of this study is to evaluate the applicability of I'mRT MatriXX for oblique beam incidence and hybrid plan verification of IMRT with original gantry angles. For the assessment of angular dependence, open fields with gantry angles in steps of 10 degrees were calculated on a CT scan of I'mRT MatriXX. For hybrid plan verification, 17 clinical IMRT plans and one rotational plan were used. Calculations were performed with pencil beam (PB), collapsed cone (CC) and Monte Carlo (MC) methods, which had...

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[Radiation therapy and medical imaging.]

Bulletin du Cancer — Wed, 23 Dec 2009 00:00:00 +0100

Authors: Berges O, Dhermain F, Bidault F The goal of radiation therapy is to deliver a high-dose of radiation to the tumour or target region to improve local control of disease and a low-dose to normal soft tissues to limit side effects. Conformal radiation therapy, intensity modulated radiotherapy (IMRT), brachytherapy and stereotactic radiosurgery have been developed to achieve the desired dose distribution. They require precise imaging of internal anatomy so that it is well adapted to the tumour and organs at risk. Indeed, morphological imaging such as computed tomography is already recommended for radiotherapy planning. But radiation oncologists are also considering other imaging modalities for treatment planning and imaging tools capable of controlling patient motion during treatm...

Hope International Centro de Radioterapia of Guatemala Becomes First in Latin America to Treat Cancer Using RapidArc(R) Radiotherapy Technology From Varian Medical Systems

HSMN NewsFeed — Tue, 22 Dec 2009 15:41:33 +0100

Patients with head and neck, rectal, and recurring prostate cancer are first to benefit from new technology for fast delivery of image-guided intensity-modulated radiotherapy (IMRT) GUATEMALA CITY, Dec. 22 (HSMN NewsFeed) -- Four cancer patients becam... Devices, OncologyVarian Medical Systems, RapidArc, radiotherapy (Source: HSMN NewsFeed)

Adverse Events Associated With Concurrent Chemoradiation Therapy in Patients With Head and Neck Cancer [Original Article]

Archives of Otolaryngology — Mon, 21 Dec 2009 20:52:36 +0100

Conclusions Patients receiving CRT experience a substantial number of treatment-related adverse events, primarily affecting oropharyngeal and laryngeal function, with improvement noted for the current IMRT protocol. Improving dental prosthetic rehabilitation and including evaluations with speech and swallowing pathologists before and during treatment may enhance patient outcomes. (Source: Archives of Otolaryngology)

Complete response to radiation therapy of orbital metastasis from hepatocellular carcinoma.

World Journal of Gastroenterology : WJG — Fri, 18 Dec 2009 19:22:13 +0100

We report the case of a 52-year-old male with known metastatic HCC, who presented with severe proptosis and diplopia. An orbital mass was identified on magnetic resonance imaging (MRI) and confirmed to have hypermetabolic activity on positron emission tomography/computed tomography. He received a palliative course of external beam radiation therapy to the right orbit. Intensity modulated radiation therapy (IMRT) was used to allow sparing of critical normal tissues in close proximity to the tumor. One month after completion of IMRT to 58 Gray in 30 fractions delivered over 6 wk, the patient had a complete clinical, radiologic (MRI) and symptomatic response. The patient continues to have local control in the orbit 1.7 years after therapy completion. All critical normal structures were kept b...

Mesothelioma Treatment Improvements with Intensity-Modulated Radiotherapy

Asbestos and Mesothelioma News — Thu, 17 Dec 2009 18:40:23 +0100

Mesothelioma researchers out of Denmark recently published a review of their experience with intensity-modulated radiotherapy (IMRT) and the incidence of pulmonary toxicity following this type of radiation. The article, titled “Pulmonary toxicity following IMRT after extrapleural pneumonectomy for malignant pleural mesothelioma,” was published in the journal Radiotherapy and Oncology and discusses the potential toxic effects of IMRT and offers recommendations on how to reduce and prevent pulmonary toxicity. “Intensity-modulated radiotherapy (IMRT) has allowed for an increase in dose to the pleural cavity and reduction in radiation doses to organs at risk. The present study reports and analyzes the incidence of fatal pulmonary toxicity in patients treated at Rigshospitalet, Copenhagen...

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A methodology for selecting the beam arrangement to reduce the intensity-modulated radiation therapy (IMRT) dose to the SPECT-defined functioning lung.

Physics in Medicine and Biology — Thu, 17 Dec 2009 00:00:00 +0100

This study aims to investigate the role of beam arrangement on both low and high doses in the functional lung. In our previous work, nine-beam IMRT plans were generated with and without SPECT guidance and compared for five patients. For the current study, the dose-function histogram (DFH) contribution for each of the nine beams for each patient was calculated. Four beams were chosen based on orientation and DFH contributions to create a SPECT-guided plan that spared the functional lung and maintained target coverage. Four-beam SPECT-guided IMRT plans reduced the F(20) and F(30) values by (16.5 +/- 6.8)% and (6.1 +/- 9.2)%, respectively, when compared to nine-beam conventional IMRT plans. Moreover, the SPECT-4F Plan reduces F(5) and F(13) for all patients by (11.0 +/- 8.2)% and (6.1 +/- 3.6...

The developing role for intensity-modulated radiation therapy (IMRT) in the non-surgical treatment of brain metastases.

The British Journal of Radiology — Thu, 17 Dec 2009 00:00:00 +0100

Authors: Edwards AA, Keggin E, Plowman PN Whole brain radiotherapy (WBRT) is the standard non-surgical treatment for brain metastatic disease, but rarely eradicates bulky metastases from most common cancers. Recent literature has demonstrated the safety and efficacy of delivering very high focal doses of radiation (by radiosurgical techniques) to the gross tumour volume of bulky brain metastases, thereby obtaining more certain local control than is achieved by WBRT. In this manuscript we report a study of 11 patients with bulky brain metastases in whom an intensity-modulated radiation therapy (IMRT) facility has been used to concomitantly boost the gross tumour volume of bulky brain metastatic disease (to 40 Gy) during a standard 30 Gy in 10 fractions WBRT schedule. No acute or subacut...

Unilateral radiotherapy for tonsil cancer: Potential dose distribution optimization with a simple two-field intensity-modulated radiation therapy beam arrangement.

Thu, 17 Dec 2009 00:00:00 +0100

CONCLUSIONS: Unilateral two-field IMRT is a simple and feasible technique providing excellent tumor coverage and optimal OAR sparing while reducing the number of MU and treatment time. PMID: 20022393 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Monte Carlo vs. Pencil Beam based optimization of stereotactic lung IMRT

Radiation Oncology — Sat, 12 Dec 2009 00:00:00 +0100

Background: The purpose of the present study is to compare 3D pencil beam (3DPB) and Monte Carlo (MC) based optimization of lung intensity-modulated stereotactic radiotherapy (lung IMSRT).Materials and methods: A 3DPB and a MC algorithm as implemented in a biological IMRT planning system were validated by film measurements in a static lung phantom. Then, they were applied for static lung IMSRT planning based on three different geometrical patient models (one phase static CT, density overwrite one phase static CT, average CT) of the same patient. Both 6 and 15 MV beam energies were used. The resulting treatment plans were compared by how well they fulfilled the prescribed optimization constraints both for the dose distributions calculated on the static patient models and for the accumulated...

ASTRO News

International Journal of Radiation Oncology * Biology * Physics — Thu, 10 Dec 2009 15:06:02 +0100

Current State of the Art Techniques for IMRT, IGRT and SBRT Symposium is scheduled for May 14-16, 2010, at the Fairmont hotel in Dallas. This unique program offers the opportunity to acquire crucial clinical education for medical professionals involved in the delivery of IMRT, IGRT and SBRT. Attendees will receive the latest information on techniques used in the adaptation of IMRT, IGRT and SBRT that the successful clinician needs to review and decide on criteria, such as patient selection, immobilization options, set-up uncertainties, multimodality imaging, image registration, motion evaluation and management, quality assurance, and correction strategies. (Source: International Journal of Radiation Oncology * Biology * Physics)

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Whole pelvic helical tomotherapy for locally advanced cervical cancer: technical implementation of IMRT with helical tomothearapy

Radiation Oncology — Thu, 10 Dec 2009 00:00:00 +0100

Conclusion: HT provides feasible clinical outcomes in locally advanced cervical cancer patients. Long-term follow-up and enroll more locally advanced cervical carcinoma patients by limiting bone marrow radiation dose with WPHT technique is warranted. (Source: Radiation Oncology)

Phenomenological modelling of second cancer incidence for radiation treatment planning.

Zeitschrift fur Medizinische Physik — Wed, 09 Dec 2009 22:54:02 +0100

This study therefore models the dose response for radiation-induced second cancer after radiation therapy of which the exact mechanisms are still unknown. A second cancer risk estimation tool for treatment planning is presented which has the potential to be used for comparison of different treatment modalities, and risk is estimated on a voxel basis for different organs in two case studies. The presented phenomenological model summarises the impact of microscopic biological processes into effective parameters of mutation and cell sterilisation. In contrast to other models, the effective radiosensitivities of mutated and non-mutated cells are allowed to differ. Based on the number of mutated cells present after irradiation, the model is then linked to macroscopic incidence by summarising mo...

Reduction of Dose Delivered to Organs at Risk in Prostate Cancer Patients via Image-Guided Radiation Therapy

International Journal of Radiation Oncology * Biology * Physics — Wed, 09 Dec 2009 00:00:00 +0100

Conclusions: Currently, margins used in IMRT plans are adequate to deliver a dose to the prostate with conventional patient positioning using skin tattoos or bony anatomy. The use of image guidance may facilitate significant reduction of planning margins. Future studies to assess the efficacy of decreasing margins and improvement of treatment-related toxicities are warranted. (Source: International Journal of Radiation Oncology * Biology * Physics)

Dose-Escalation Using IMRT For Prostate Cancer - Evaluation Of The Dose Distribution Detected Simultaneous Integrated Boost

Health News from Medical News Today — Sat, 05 Dec 2009 09:00:00 +0100

UroToday.com - Randomized three-dimensional conformal radiotherapy dose escalation studies have consistently shown improved biochemical control rates for prostate cancer. This benefit was associated with the problem of increased rectal toxicity. The increasing implementation of image-guided radiotherapy (IGRT) allows a reduction of safety margins around the clinical target volume (CTV). Thus, the same or improved local tumour control with lower rectal toxicity due to reduced rectal volume within the target volume can be expected... (Source: Health News from Medical News Today)

Dose-Escalation Using IMRT For Prostate Cancer - Evaluation Of The Dose Distribution Detected Simultaneous Integrated Boost

Radiology / Nuclear Medicine News From Medical News Today — Sat, 05 Dec 2009 09:00:00 +0100

UroToday.com - Randomized three-dimensional conformal radiotherapy dose escalation studies have consistently shown improved biochemical control rates for prostate cancer. This benefit was associated with the problem of increased rectal toxicity. The increasing implementation of image-guided radiotherapy (IGRT) allows a reduction of safety margins around the clinical target volume (CTV)... (Source: Radiology / Nuclear Medicine News From Medical News Today)

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Dose-Escalation Using IMRT For Prostate Cancer - Evaluation Of The Dose Distribution Detected Simultaneous Integrated Boost

Radiology / Nuclear Medicine News From Medical News Today — Sat, 05 Dec 2009 09:00:00 +0100

UroToday.com - Randomized three-dimensional conformal radiotherapy dose escalation studies have consistently shown improved biochemical control rates for prostate cancer. This benefit was associated with the problem of increased rectal toxicity. The increasing implementation of image-guided radiotherapy (IGRT) allows a reduction of safety margins around the clinical target volume (CTV)... (Source: Radiology / Nuclear Medicine News From Medical News Today)

Fighting Prostate Cancer With Speed And Accuracy: RapidArc(R) Radiotherapy Available At The Delaware Valley Urology Cancer Treatment Center

Health News from Medical News Today — Wed, 02 Dec 2009 09:00:00 +0100

Former New Jersey Assemblyman Francis Bodine was surprised and delighted when his radiotherapy treatment sessions for prostate cancer went from about 20 minutes each day to less than five. Midway through his course of treatment, doctors at the Delaware Valley Urology Cancer Center acquired the region's first RapidArc® radiotherapy technology from Varian Medical Systems (NYSE: VAR), making it possible for them to deliver advanced intensity-modulated radiotherapy (IMRT) treatments two to eight times faster than was previously possible... (Source: Health News from Medical News Today)

Fighting Prostate Cancer With Speed and Accuracy: RapidArc(R) Radiotherapy Available at the Delaware Valley Urology Cancer Treatment Center

HSMN NewsFeed — Tue, 01 Dec 2009 22:18:17 +0100

CHERRY HILL, N.J., Dec. 1 (HSMN NewsFeed) -- Former New Jersey Assemblyman Francis Bodine was surprised and delighted when his radiotherapy treatment sessions for prostate cancer went from about 20 minutes each day to less than five. Midway through his c... Devices, OncologyVarian Medical Systems, RapidArc, radiotherapy, IMRT (Source: HSMN NewsFeed)

Quantitative Ultrasonic Elastography for Gel Dosimetry

Ultrasound in Medicine and Biology — Mon, 30 Nov 2009 00:00:00 +0100

Abstract: Advanced radiation techniques such as intensity-modulated radiotherapy (IMRT) for complex geometries in which targets are close to organs at risk have been introduced in radiation therapy, creating a need for procedures that allow easy three-dimensional (3-D) measurement of dose for verification purposes. Polymer gels that change their material properties when irradiated have been suggested for such use. For example, the change in their magnetic properties has been thoroughly investigated with magnetic resonance imaging (MRI). Also, we have previously shown that the mechanical stiffness, i.e., Young's modulus, of these gels changes with dose. This finding prompted us to assess whether we can image a radiation-induced stiffness distribution with quantitative ultrasound elastograph...

Advances In Radiation Therapy Enable Doctors To Improve The Quality Of Treatments For Patients With Head And Neck Cancer

Cancercompass News: Other Cancer — Tue, 24 Nov 2009 00:00:00 +0100

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Survey on human papillomavirus/p16 screening use in oropharyngeal carcinoma patients in the United States

Cancer — Tue, 24 Nov 2009 00:00:00 +0100

The objective of the current study was to assess how different practices across the United States treat patients with OC with respect to screening for HPV DNA or p16.Five hundred forty-two randomly selected radiation oncologists were sent an 11-question survey by email regarding the use of HPV/p16 screening in OC. The questionnaire addressed demographics of the practice, intensity-modulated radiotherapy (IMRT) use, screening practices for HPV DNA or p16, which year this began, the use of HPV or p16 data to direct patient care, and future plans for its use if it had not already been instituted.One hundred ninety-two responses (39.6%) were received. Thirty-five percent of respondents (67 of 188) reported screening for HPV DNA routinely, whereas 4.8% of respondents (9 of 188) reported screeni...

Integrated-boost IMRT or 3-D-CRT using FET-PET based auto-contoured target volume delineation for glioblastoma multiforme - a dosimetric comparison

Radiation Oncology — Mon, 23 Nov 2009 00:00:00 +0100

Background: Biological brain tumor imaging using O-(2-[18F]fluoroethyl)-L-tyrosine (FET)-PET combined with inverse treatment planning for locally restricted dose es-calation in patients with glioblastoma multiforme seems to be a promising approach.The aim of this study was to compare inverse with forward treatment planning for an integrated boost dose application in patients suffering from a glioblastoma multi-forme, while biological target volumes are based on FET-PET and MRI data sets. Methods: In 16 glioblastoma patients an intensity-modulated radiotherapy technique comprising an integrated boost (IB-IMRT) and a 3-dimensional conventional radio-therapy (3D-CRT) technique were generated for dosimetric comparison. FET-PET, MRI and treatment planning CT (P-CT) were co-registrated. The inte...

University College Hospital In London Introduces Treatments Delivering Faster Form Of Radiotherapy

Health News from Medical News Today — Fri, 20 Nov 2009 08:00:00 +0100

Two female brain tumor patients have become the first people in the south of England to be treated using a faster form of radiotherapy that extends more advanced care to more patients. RapidArc technology from Varian Medical Systems (NYSE: VAR) makes it possible to deliver image-guided IMRT (intensity modulated radiotherapy) two to eight times faster than is possible with conventional IMRT. (Source: Health News from Medical News Today)

University College Hospital In London Introduces Treatments Delivering Faster Form Of Radiotherapy

Radiology / Nuclear Medicine News From Medical News Today — Fri, 20 Nov 2009 08:00:00 +0100

Evaluation of a biplanar diode array dosimeter for quality assurance of step-and-shoot IMRT.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

We described and characterized a novel biplanar diode array, and demonstrated its applicability to dosimetric QA of the step-and-shoot IMRT. It is the first commercially available device of its kind specifically designed for measurements at varying gantry angles. The detector consists of a cylindrical PMMA phantom with two orthogonal detector boards. There are a total of 1069 p-type 1 mm wide diode detectors covering the measurement area of 20 x 20 cm2 in each of the measurement planes. The orthogonal detector arrays ensure that the dose modulation information is not lost regardless of the beam incidence angle. For absolute calibration, the dose to the reference detector is calculated at the appropriate SSD and radiological depth by the treatment planning system and is scaled by the measur...

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Comparing planning time, delivery time and plan quality for IMRT, RapidArc and Tomotherapy.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

Authors: Oliver M, Ansbacher W, Beckham WA The purpose of this study is to examine plan quality, treatment planning time, estimated treatment delivery time and other dose metrics for 5 and 9 field sliding window IMRT (IMRT5 and IMRT9), single and dual arc Rapid Arc (RA1 and RA2) and Tomotherapy (TOMO). Four cylindrical virtual phantoms were created each with its own distinct set of contours. The contour sets were 2D contours on the axial slice extended in the superior-inferior direction. The prescription dose in all cases was 2 Gy per fraction. IMRT plans were created with 5 or 9 equally spaced beams and RA plans were created with either 1 or 2 complete rotations of the gantry. TOMO plans were created with typical planning parameters. Plans were evaluated based on the ability to meet d...

Direct machine parameter optimization for intensity modulated radiation therapy (IMRT) of oropharyngeal cancer - a planning study.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

Authors: Dobler B, Koelbl O, Bogner L, Pohl F The purpose of the study was to investigate the potential of direct machine parameter optimization (DMPO) to achieve parotid sparing without compromising target coverage in IMRT of oropharyngeal cancer as compared to fluence modulation with subsequent leaf sequencing (IM) and forward planned 2-step arc therapy (IMAT). IMRT plans were generated for 10 oropharyngeal cancer patients using DMPO and IM. The resulting dose volume histograms (DVH) were evaluated with regard to compliance with the dose volume objectives (DVO) and plan quality. DMPO met the DVO for the targets better than IM but violated the DVO to the parotids in some cases. DMPO provided better target coverage and dose homogeneity than IM and comparable to IMAT. Dose to the paroti...

Algorithm for correcting optimization convergence errors in Eclipse.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

Authors: Zacarias AS, Mills MD IMRT plans generated in Eclipse use a Dose Volume Optimizer (DVO) algorithm to evaluate dose for optimization and a more accurate algorithm for a final Volume Dose (VD) calculation, the Analytical Anisotropic Algorithm (AAA). The use of the DVO introduces Optimization Convergence Errors (OCE's) into an IMRT plan. Eclipse has a feature where optimization may be performed on top of an existing base plan. When the base plan is an optimized IMRT plan, a second optimization can compensate for errors in the base plan. Errors in the base plan are demonstrated to originate in the DVO. An IMRT plan containing the same field arrangement as the initial base plan may be generated by adding the initial plan optimal fluence to the dose correcting plan optimal fluence. ...

Effect of Collimator and Couch Angle Change on Breast IMRT Dose Distributions.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

The objective of this work is to investigate the effects of the collimator and the couch angle change on the dose distribution for breast cancer treatment using intensity modulated tangential photon beams, and thus to determine the clinical acceptable range of the angle change for routine treatment. Ten breast cases treated with intensity modulated tangential photon beams were analyzed in this study. Patient-specific CT data and the RTP files obtained from our home-grown Monte Carlo based breast IMRT treatment planning system were used for IMRT dose re-calculation with collimator or couch angle changes. The isodose distributions and DVHs were compared with the original plans and the effects of the collimator and couch angle change to breast IMRT dose distributions were evaluated. Our resul...

The effect of interfraction prostate motion on IMRT plans: a dose-volume histogram analysis using a Gaussian error function model.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

Authors: Chow JC, Jiang R, Markel D The Gaussian error function model, containing pairs of error and complementary error functions, was used to carry out cumulative dose-volume histogram (cDVH) analysis on prostate intensity modulated radiation therapy (IMRT) plans with interfraction prostate motion. Cumulative DVHs for clinical target volumes (CTVs) shifted in the anterior-posterior directions based on a 7-beam IMRT plan were calculated and modeled using the Pinnacle3 treatment planning system and a Gaussian error function, respectively. As the parameters in the error function model, namely, a, b and c were related to the shape of the cDVH curve, evaluation of cDVHs corresponding to the prostate motion based on the model parameters becomes possible as demonstrated in this study. It wa...

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A diagnostic tool for basic daily quality assurance of a Tomotherapy Hi*Art machine.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

Conclusion: This tool makes it possible to perform an easy-to-use and fast basic daily quality assurance check featuring an output as well as an energy evaluation. Ideally this tool should offer also the combined dosimetry check of jaw width, couch speed, leaf latency, output, leaf/gantry synchrony and lasers. This will be investigated in the future. PMID: 19918225 [PubMed - in process] (Source: Journal of Applied Clinical Medical Physics)

Characterization of cylindrical ionization chambers for patient specific IMRT QA.

Journal of Applied Clinical Medical Physics — Fri, 20 Nov 2009 06:02:03 +0100

Authors: Fraser DJ, Parker W, Seuntjens J Proven conventional dosimetry techniques do not provide accuracy and precision in the measurement of inverse planned intensity modulated radiation therapy (IMRT) fields. Dynamic and step-and-shoot multileaf collimation (DMLC/SMLC) challenge current ionization chamber dosimetry practices. Ionization chamber performance in these fields is evaluated for three cylindrical chambers of varying volumes (PinPoint (PP): 0.015 cm3, IC10: 0.13 cm3, Farmer type NE2571 (FT): 0.69 cm3) in terms of measurement reproducibility, dose measurement linearity, and IMRT dose measurements. Fifty IMRT patient specific quality assurance dose measurements were performed with each chamber. DMLC measurements are compared between chambers, and to dose calculations from a c...

Comparison of IMRT planning with two-step and one-step optimization: a strategy for improving therapeutic gain and reducing the integral dose.

Physics in Medicine and Biology — Fri, 20 Nov 2009 05:56:05 +0100

Authors: Abate A, Pressello MC, Benassi M, Strigari L The aim of this study was to evaluate the effectiveness and efficiency in inverse IMRT planning of one-step optimization with the step-and-shoot (SS) technique as compared to traditional two-step optimization using the sliding windows (SW) technique. The Pinnacle IMRT TPS allows both one-step and two-step approaches. The same beam setup for five head-and-neck tumor patients and dose-volume constraints were applied for all optimization methods. Two-step plans were produced converting the ideal fluence with or without a smoothing filter into the SW sequence. One-step plans, based on direct machine parameter optimization (DMPO), had the maximum number of segments per beam set at 8, 10, 12, producing a directly deliverable sequence. Mor...

Dose-Rate Effects When Estimating Risks for Second Malignancies: In Regard to Fontenot et al (Int J Radiat Oncol Biol Phys 2009;74:616–622)

International Journal of Radiation Oncology * Biology * Physics — Thu, 19 Nov 2009 15:21:30 +0100

To the Editor: In the work by Fontenot et al. , the risk for developing a second malignancy after prostate radiation therapy was estimated for proton therapy and intensity-modulated X-ray therapy (IMRT). The authors conclude that proton therapy can reduce the risk for a second cancer when compared with IMRT. (Source: International Journal of Radiation Oncology * Biology * Physics)

Advanced kernel methods vs. Monte Carlo-based dose calculation for high energy photon beams

Radiotherapy and Oncology — Thu, 19 Nov 2009 00:00:00 +0100

Conclusion: All TPS investigated in this study demonstrated accurate dose calculation in homogenous and heterogeneous phantoms. Commercially available TPS with Monte Carlo option performed best in heterogeneous phantoms. However, the difference between the CC and the MC algorithms was found to be small. (Source: Radiotherapy and Oncology)

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[68Ga]-DOTATOC-PET/CT for meningioma IMRT treatment planning

Radiation Oncology — Wed, 18 Nov 2009 00:00:00 +0100

Conclusion: DOTATOC-PET/CT information may strongly complement patho-anatomical data from MRI and CT in cases with complex meningioma and is thus helpful for improved target volume delineation especially for skull base manifestations and recurrent disease after surgery. (Source: Radiation Oncology)

Intensity-modulated radiotherapy for recurrent and second primary head and neck cancer in previously irradiated territory

Radiotherapy and Oncology — Wed, 18 Nov 2009 00:00:00 +0100

Conclusions: High-dose IMRT for recurrent and second primary head and neck cancer in previously irradiated territory leads to ≈20% long-term survival in a non-selected patient population. Identification of patients who would benefit most of curative IMRT is warranted. (Source: Radiotherapy and Oncology)

Advanced kernel methods vs. Monte Carlo-based dose calculation for high energy photon beams.

Tue, 17 Nov 2009 00:00:00 +0100

CONCLUSION: All TPS investigated in this study demonstrated accurate dose calculation in homogenous and heterogeneous phantoms. Commercially available TPS with Monte Carlo option performed best in heterogeneous phantoms. However, the difference between the CC and the MC algorithms was found to be small. PMID: 19926153 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Postoperative Reirradiation for Mucosal Head and Neck Squamous Cell Carcinomas [Original Article]

Archives of Otolaryngology — Mon, 16 Nov 2009 20:51:31 +0100

Conclusions Reirradiation represents the only chance for cure in patients with unresectable disease. After surgery, reirradiation is performed in patients at high risk of locoregional recurrence and may increase acute toxic effects. However, free-flap reconstruction may reduce toxic effects. Functional outcomes have declined since 2000 likely because of the addition of concurrent platinum-based chemotherapy. Future research may define the subpopulation of postoperative patients for whom survival benefits most outweigh reirradiation toxic effects. (Source: Archives of Otolaryngology)

New technology unveiled at ASTRO 2009

Cancer Network — Mon, 16 Nov 2009 12:00:00 +0100

CHICAGO—Accuray introduced the CyberKnife VSI System. The system is designed to also include conventionally fractionated robotic intensity-modulated radiation therapy. (Source: Cancer Network)

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Intensity-modulated radiotherapy for recurrent and second primary head and neck cancer in previously irradiated territory.

Mon, 16 Nov 2009 00:00:00 +0100

CONCLUSIONS: High-dose IMRT for recurrent and second primary head and neck cancer in previously irradiated territory leads to approximately 20% long-term survival in a non-selected patient population. Identification of patients who would benefit most of curative IMRT is warranted. PMID: 19919885 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Intensity-modulated radiation therapy for anal cancer.

Oncology (Williston Park, N.Y.) — Sun, 15 Nov 2009 00:00:00 +0100

Authors: Czito BG, Pepek JM, Meyer JJ, Yoo S, Willett CG The contemporary treatment of anal cancer is combined-modality therapy with radiation therapy, fluorouracil, and mitomycin. This therapy results in long-term disease-free survival and sphincter preservation in the majority of patients. Tempering these positive results is the high rate of treatment-related morbidity associated with chemoradiation therapy for anal cancer. The use of intensity-modulated radiation therapy (IMRT) has the potential to reduce acute and chronic treatment-related toxicity, minimize treatment breaks, and potentially improve disease-related outcomes by permitting radiation dose escalation in selected cases. PMID: 20017291 [PubMed - in process] (Source: Oncology (Williston Park, N.Y.))

IMRT delivers high doses to prostate with satisfactory functional outcomes

MedWire News - Prostate Cancer — Sat, 14 Nov 2009 13:47:19 +0100

Prostate cancer patients treated with intensity-modulated radiation therapy experience no significant worsening of urinary, sexual, or bowel function 5 years after treatment, Japanese researchers report. (Source: MedWire News - Prostate Cancer)

Advances In Radiation Therapy Enable Doctors To Improve The Quality Of Treatments For Patients With Head And Neck Cancer

Health News from Medical News Today — Sat, 14 Nov 2009 09:00:00 +0100

Advances In Radiation Therapy Enable Doctors To Improve The Quality Of Treatments For Patients With Head And Neck Cancer

Cancer / Oncology News From Medical News Today — Sat, 14 Nov 2009 09:00:00 +0100

Clinical studies suggest that advanced treatments like intensity-modulated radiotherapy (IMRT) and image-guided radiotherapy (IGRT) are enabling radiation oncologists to enhance post-treatment health-related quality of life for patients with head and neck cancer. In an educational session for radiotherapy professionals, delivered by two noted experts during the annual meeting of the American Society for Radiation Oncology (ASTRO) in Chicago last week, Avraham Eisbruch, M.D. (Source: Cancer / Oncology News From Medical News Today)

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Advances in Radiation Therapy Enable Doctors to Improve the Quality of Treatments for Patients With Head and Neck Cancer

HSMN NewsFeed — Fri, 13 Nov 2009 15:53:57 +0100

Noted clinical experts detail recent developments at the annual ASTRO meeting in Chicago PALO ALTO, Calif., Nov. 13 (HSMN NewsFeed) -- Clinical studies suggest that advanced treatments like intensity-modulated radiotherapy (IMRT) and image-guided radi... Devices, OncologyVarian Medical Systems, image-guided radiotherapy, IGRT, radiotherapy (Source: HSMN NewsFeed)

IMRT delivers high doses to prostate with satisfactory functional outcomes

MedWire News - Oncology — Fri, 13 Nov 2009 00:00:00 +0100

Clinical-Dosimetric Analysis of Measures of Dysphagia including Gastrostomy-tube Dependence among Head and Neck Cancer Patients Treated Definitively by Intensity-Modulated Radiotherapy with Concurrent Chemotherapy

Radiation Oncology — Thu, 12 Nov 2009 00:00:00 +0100

Conclusion: Our analysis suggests that adhering to the following parameters may decrease the risk of prolonged GT dependence and dysphagia: IPC V65 < 15%, IPC V60 < 40%, IPC Dmean < 55 Gy, and CPI Dmax < 60 Gy. (Source: Radiation Oncology)

Incidence and Correlates of Radiation Dermatitis in Children and Adolescents Receiving Radiation Therapy for the Treatment of Paediatric Sarcomas

Clinical Oncology — Mon, 09 Nov 2009 15:31:42 +0100

Abstract: Aims: To investigate the relationship between the maximum grade of skin toxicity, radiation dose and clinical variables in children receiving treatment for sarcomas involving the bone and soft tissue.Materials and methods: Between January 2003 and July 2006, 82 patients with musculoskeletal tumours on an Institutional Review Board (IRB)-approved prospective study at St. Jude Children's Research Hospital received three-dimensional conformal or intensity-modulated radiation therapy for local tumour control. Radiation dermatitis was graded according to the National Cancer Institute's Common Toxicity Criteria version 2.0 during and after radiation therapy. The dose to the skin was calculated for each patient from the radiation treatment plan.Results: The radiation doses delivered to ...

A Dosimetric Selectivity Intercomparison of HDR Brachytherapy, IMRT and Helical Tomotherapy in Prostate Cancer Radiotherapy

Strahlentherapie und Onkologie — Mon, 09 Nov 2009 06:59:53 +0100

Conclusion: HDR-BT offers better conformality in comparison with HT and IMRT and reduces the volume of healthy tissue receiving a low dose. Content Type Journal ArticleCategory Original ArticleDOI 10.1007/s00066-009-2009-5Authors Johanne Hermesse, Liège University Hospital Department of Radiation Oncology Liège BelgiumSylvie Biver, Liège University Hospital Department of Radiation Oncology Liège BelgiumNicolas Jansen, Liège University Hospital Department of Radiation Oncology Liège BelgiumEric Lenaerts, Liège University Hospital Department of Medical Physics Liège BelgiumNathalie De Patoul, St Luc University Hospital Department of Medical Physics Brussels BelgiumStefaan Vynckier, St Luc University Hospital Department of Medical Physics Brussels BelgiumPhilipp...

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Evaluation of the impact of dental artefacts on intensity-modulated radiotherapy planning for the head and neck

Radiotherapy and Oncology — Mon, 09 Nov 2009 00:00:00 +0100

Conclusions: Use of an extended CT/density look-up table together with a simple manual bulk density correction reduces the impact of dental artefacts on head and neck IMRT planning to acceptable levels. (Source: Radiotherapy and Oncology)

Radiotherapy of malignant gliomas: Comparison of volumetric single arc technique (RapidArc), dynamic intensity-modulated technique and 3D conformal technique

Radiotherapy and Oncology — Mon, 09 Nov 2009 00:00:00 +0100

Conclusions: If PTV is distant to OAR, the use of 3D conformal technique is sufficient. Otherwise an intensity-modulated technique should be used. RapidArc was faster than conventional IMRT and should be preferred if PTV coverage is adequate. (Source: Radiotherapy and Oncology)

Med Tec Inc - CIVCO MTAPSID2932 Type-S Thermoplastic - Class 3 Recall

Medical Device Recalls since July 07, 2006 — Sat, 07 Nov 2009 02:00:05 +0100

CIVCO MTAPSID2932 Type-S Thermoplastic, Disposable nonsterile (48.3 cm) IMRT Style 29 thermoplastic (3.2 mm), Ref. MTAPSID2932, disposable frame mask, 5 per box. The firm name on the label is CIVCO, Orange City, IA. Intended to be used for patient fixation. (Source: Medical Device Recalls since July 07, 2006)

Evaluation of the impact of dental artefacts on intensity-modulated radiotherapy planning for the head and neck.

Fri, 06 Nov 2009 00:00:00 +0100

CONCLUSIONS: Use of an extended CT/density look-up table together with a simple manual bulk density correction reduces the impact of dental artefacts on head and neck IMRT planning to acceptable levels. PMID: 19897267 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Radiotherapy of malignant gliomas: Comparison of volumetric single arc technique (RapidArc), dynamic intensity-modulated technique and 3D conformal technique.

Fri, 06 Nov 2009 00:00:00 +0100

CONCLUSIONS: If PTV is distant to OAR, the use of 3D conformal technique is sufficient. Otherwise an intensity-modulated technique should be used. RapidArc was faster than conventional IMRT and should be preferred if PTV coverage is adequate. PMID: 19897266 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

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Impact of target volumes and radiation technique on loco-regional control and survival for patients with unilateral cervical lymph node metastases from an unknown primary

Radiotherapy and Oncology — Fri, 06 Nov 2009 00:00:00 +0100

Conclusions: Retrospective comparisons between bilateral and unilateral neck radiotherapies did not show differences in terms of loco-regional control and survival. However, patient’s local regional control and survival are significantly improved after 3D-CRT or IMRT. (Source: Radiotherapy and Oncology)

A treatment planning study comparing helical tomotherapy with intensity-modulated radiotherapy for the treatment of anal cancer

Radiotherapy and Oncology — Fri, 06 Nov 2009 00:00:00 +0100

Conclusions: HT and IMRT techniques achieved comparable target dose coverage and organ sparing, whereas HT plans were more homogeneous for both men and women. (Source: Radiotherapy and Oncology)

Mesothelioma Trimodality Therapy Benefits Patients

Asbestos and Mesothelioma News — Thu, 05 Nov 2009 14:53:07 +0100

In a study recently published in The Annals of Thoracic Surgery, mesothelioma researchers found a trimodality therapeutic approach of chemotherapy, surgery and radiation to be effective in treating malignant pleural mesothelioma. Mesothelioma is a cancer caused almost exclusively by asbestos exposure. A long latency period of 20 to 50 years complicates the diagnostic process and usually leads to a diagnosis at a late stage of cancer development. Because most cases of malignant mesothelioma are diagnosed in a late stage of development, treatment options are often limited to palliative measures intended to improve quality of life. Researchers are avidly searching for a cure for this rare cancer, as current treatment therapies typically fail to fully combat the cancer. According to the study�...

Impact of target volumes and radiation technique on loco-regional control and survival for patients with unilateral cervical lymph node metastases from an unknown primary.

Wed, 04 Nov 2009 00:00:00 +0100

CONCLUSIONS: Retrospective comparisons between bilateral and unilateral neck radiotherapies did not show differences in terms of loco-regional control and survival. However, patient's local regional control and survival are significantly improved after 3D-CRT or IMRT. PMID: 19892420 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

A treatment planning study comparing helical tomotherapy with intensity-modulated radiotherapy for the treatment of anal cancer.

Wed, 04 Nov 2009 00:00:00 +0100

CONCLUSIONS: HT and IMRT techniques achieved comparable target dose coverage and organ sparing, whereas HT plans were more homogeneous for both men and women. PMID: 19896229 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

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Image guided dose escalated prostate radiotherapy: still room to improve

Radiation Oncology — Tue, 03 Nov 2009 00:00:00 +0100

Conclusions: IGRT to 79.8 Gy results in favourable rates of late toxicity compared with published non-IGRT treated cohorts. Future avenues of investigation for toxicity reduction include IMRT, margin reduction, and dose modulation targeted to sites of disease burden. Further work is required to maximize efficacy beyond that achieved through radiation dose escalation alone. (Source: Radiation Oncology)

Five-year Follow-up of Health-related Quality of Life after Intensity-modulated Radiation Therapy for Prostate Cancer

Japanese Journal of Clinical Oncology — Mon, 02 Nov 2009 11:24:26 +0100

Conclusions IMRT can provide the possibility to deliver a high irradiation dose to the prostate with satisfactory functional outcomes for long-term periods. (Source: Japanese Journal of Clinical Oncology)

Anaplastic thyroid cancer: Clinical outcomes with conformal radiotherapy

Head and Neck — Mon, 02 Nov 2009 00:00:00 +0100

Conclusions.Outcomes for anaplastic thyroid cancer treated with 3DRT or IMRT remain equivalent to historical results. Healthy patients with localized disease who tolerate full dose irradiation can potentially enjoy prolonged survival. Biologically targeted radiosensitization merits prioritized investigation. © 2009 Wiley Periodicals, Inc. Head Neck, 2009 (Source: Head and Neck)

Critical Appraisal of Volumetric Modulated Arc Therapy in Stereotactic Body Radiation Therapy for Metastases to Abdominal Lymph Nodes

International Journal of Radiation Oncology * Biology * Physics — Mon, 02 Nov 2009 00:00:00 +0100

Purpose: A planning study was performed comparing volumetric modulated arcs, RapidArc (RA), fixed beam IMRT (IM), and conformal radiotherapy (CRT) with multiple static fields or short conformal arcs in a series of patients treated with hypofractionated stereotactic body radiation therapy (SBRT) for solitary or oligo-metastases from different tumors to abdominal lymph nodes.Methods and Materials: Fourteen patients were included in the study. Dose prescription was set to 45 Gy (mean dose to clinical target volume [CTV]) in six fractions of 7.5 Gy. Objectives for CTV and planning target volume (PTV) were as follows: Dosemin >95%, Dosemax (Source: International Journal of Radiation Oncology * Biology * Physics)

Correlation between dose to the pharyngeal constrictors and patient quality of life and late dysphagia following chemo-IMRT for head and neck cancer

Radiotherapy and Oncology — Mon, 02 Nov 2009 00:00:00 +0100

Abstract: Purpose: Aim of this study was to correlate dose to pharyngeal constrictors (PC) with subjective and observer-based assessments of swallowing in patients with head and neck cancer undergoing concomitant chemo-IMRT.Materials and methods: Dose–volume histograms (DVHs) for superior constrictor (SC), middle constrictor (MC) and inferior constrictor (IC) were generated for 37 patients. Mean doses to SC, MC and IC were correlated to objective dysphagia grade (1year, RTOG scoring) and global, total physical (TP) and most relevant components of the physical section (P6, P8) of the MD Anderson dysphagia inventory (MDADI) which was evaluated post-treatment. Odds ratios of dysphagia (>grade 0), poor global ( (Source: Radiotherapy and Oncology)

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Accuray Introduces the CyberKnife(R) VSI(TM) System

HSMN NewsFeed — Sun, 01 Nov 2009 21:37:36 +0100

New Capabilities Extend CyberKnife Treatment Options to Include Robotic IMRT SUNNYVALE, Calif., Nov. 1 (HSMN NewsFeed) -- Accuray Incorporated (Nasdaq: ARAY ), a global leader in the field of radiosurgery, announced today the introduction of the Cyber... Devices, OncologyAccuray, CyberKnife, CyberKnife VSI, radiosurgery, radiotherapy (Source: HSMN NewsFeed)

Radiation therapy for urologic malignancies in the elderly.

Urologic Oncology — Sun, 01 Nov 2009 00:00:00 +0100

This article also reviews the role of radiotherapy in older patients with other urologic malignancies, such as testicular tumor, bladder cancer, renal carcinoma, and penile cancer. PMID: 19879475 [PubMed - in process] (Source: Urologic Oncology)

Correlation between dose to the pharyngeal constrictors and patient quality of life and late dysphagia following chemo-IMRT for head and neck cancer.

Sat, 31 Oct 2009 00:00:00 +0100

CONCLUSION: This study did not find a statistically significant correlation between radiation dose to the PC and observer-assessed dysphagia grade or patient-reported MDADI questionnaire at 1year. PMID: 19883951 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

Radiation therapy for urologic malignancies in the elderly

Urologic Oncology: Seminars and Original Investigations — Fri, 30 Oct 2009 15:30:08 +0100

This article also reviews the role of radiotherapy in older patients with other urologic malignancies, such as testicular tumor, bladder cancer, renal carcinoma, and penile cancer. (Source: Urologic Oncology: Seminars and Original Investigations)

Interfractional Uncertainty in the Treatment of Pancreatic Cancer With Radiation

International Journal of Radiation Oncology * Biology * Physics — Fri, 30 Oct 2009 00:00:00 +0100

Conclusions: There is substantial residual uncertainty after alignment to bony anatomy when radiating pancreatic tumors using respiratory gating. Bony anatomy matched tumor position in only 20% of the radiation treatments. If bony alignment is used in conjunction with respiratory gating without implanted fiducials, treatment margins need to account for this uncertainty. (Source: International Journal of Radiation Oncology * Biology * Physics)

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Intensity-Modulated and 3D-Conformal Radiotherapy for Whole-Ventricular Irradiation as Compared With Conventional Whole-Brain Irradiation in the Management of Localized Central Nervous System Germ Cell Tumors

International Journal of Radiation Oncology * Biology * Physics — Fri, 30 Oct 2009 00:00:00 +0100

Conclusions: Although IMRT is associated with increased radiation doses to peripheral areas of the body, its use can spare a significant amount of normal central nervous system tissue compared with 3D-CRT or WBI in the setting of CNSGCT treatment. (Source: International Journal of Radiation Oncology * Biology * Physics)

Strategies for Online Organ Motion Correction for Intensity-Modulated Radiotherapy of Prostate Cancer: Prostate, Rectum, and Bladder Dose Effects

International Journal of Radiation Oncology * Biology * Physics — Mon, 26 Oct 2009 15:43:47 +0100

Conclusions: With online correction of both translations and rotations, a 4-mm margin was sufficient for 15 of 19 patients, whereas the remaining four patients had an underdosed CTV volume (Source: International Journal of Radiation Oncology * Biology * Physics)

A fast radiotherapy paradigm for anal cancer with volumetric modulated arc therapy (VMAT)

Radiation Oncology — Sun, 25 Oct 2009 00:00:00 +0100

Conclusion: VMAT provides treatment plans with high conformity and homogeneity equivalent to step-and-shoot-IMRT for this mono-concave treatment volume. Short treatment delivery time and low primary MU are the most important advantages. (Source: Radiation Oncology)

Single crystal chemical vapor deposited diamond detectors for intensity-modulated radiation therapy applications

Journal of Applied Physics — Fri, 23 Oct 2009 15:25:21 +0100

We report here on first intensity-modulated radiation therapy (IMRT) clinical tests performed at the Gustave Roussy Institute in France using one small (0.117 mm) synthetic single crystal diamond detector (SCDD). We report the comparison between the point doses evaluated with our detector, with a P ... [J. Appl. Phys. 106, 084509 (2009)] published Fri Oct 23, 2009. (Source: Journal of Applied Physics)

A study of middle ear function in the treatment of nasopharyngeal carcinoma with IMRT technique

Radiotherapy and Oncology — Fri, 23 Oct 2009 00:00:00 +0100

This study evaluates the difference in damage to middle ear function with CRT and IMRT techniques in the treatment of nasopharyngeal carcinoma (NPC). We explore the isthmus of the Eustachian tube (ET) as the key anatomic site for the prevention of radiation-induced otitis media with effusion.Methods and materials: Eighty-two patients with NPC were divided into two groups: 40 patients treated with CRT and 42 patients treated with IMRT. The difference between dosage over the middle ear cavity and the isthmus of the ET was evaluated in both CRT group and IMRT group. All patients underwent hearing tests including pure tone audiometry and impedance audiometry before and after RT.Results: The dosage difference to the middle ear cavity and isthmus between these two groups was statistically signif...

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Dosimetric study of five-field intensity-modulated radiotherapy compared with conventional three-dimensional conformal radiotherapy for rectal cancer

The Chinese-German Journal of Clinical Oncology — Wed, 21 Oct 2009 19:13:59 +0100

Conclusion Five-field IMRT-plan is better than 3DCRT-plan in the conformity and the dose homogeneity within target volume and also better in sparing the small bowel and bladder. Content Type Journal ArticleDOI 10.1007/s10330-009-0130-7Authors Bo Yao, General Hospital of Beijing Military Command Department of Radiation Oncology Beijing 100700 ChinaMingmin Zheng, General Hospital of Beijing Military Command Department of Radiation Oncology Beijing 100700 ChinaPing Wang, General Hospital of Beijing Military Command Department of Radiation Oncology Beijing 100700 China Journal The Chinese-German Journal of Clinical OncologyOnline ISSN 1613-9089Print ISSN 1610-1979 Journal Volume Volume 8 Journal Issue Volume 8, Number 10 / October, 2009 (Source: The Chinese-...

A generalized inverse planning tool for volumetric-modulated arc therapy.

Physics in Medicine and Biology — Wed, 21 Oct 2009 15:08:13 +0100

Authors: Cao D, Afghan MK, Ye J, Chen F, Shepard DM The recent development in linear accelerator control systems, named volumetric-modulated arc therapy (VMAT), has generated significant interest in arc-based intensity-modulated radiation therapy (IMRT). The VMAT delivery technique features simultaneous changes in dose rate, gantry angle and gantry rotation speed as well as multi-leaf collimator (MLC) leaf positions while radiation is on. In this paper, we describe a generalized VMAT planning tool that is designed to take full advantage of the capabilities of the new linac control systems. The algorithm incorporates all of the MLC delivery constraints such as restrictions on MLC leaf interdigitation and the MLC leaf velocity constraints. A key feature of the algorithm is that it is abl...

A study of middle ear function in the treatment of nasopharyngeal carcinoma with IMRT technique.

Wed, 21 Oct 2009 00:00:00 +0100

CONCLUSIONS: IMRT may have better protected the middle ear function compared with the CRT technique, even with larger fraction sizes than for the conventional CRT technique. PMID: 19853315 [PubMed - as supplied by publisher] (Source: Radiotherapy and Oncology : journal of the European Society for Therapeutic Radiology and Oncology)

High-dose-rate surface brachytherapy to boost elongated, curvilinear incisional scars after extrapleural pneumonectomy for malignant pleural mesothelioma treated with adjuvant intensity-modulated radiation therapy

Brachytherapy — Wed, 21 Oct 2009 00:00:00 +0100

Conclusions: Surface HDR brachytherapy is a viable option for supplemental dose to incisional scars at risk of local recurrence after EPP for MPM. Advantages over electron beam therapy include avoidance of field abutments and feathering, less tissue–bone interface dose uncertainty and reproducibility of treatment delivery. (Source: Brachytherapy)