Radiation Oncology via MedWorm.com

A National Survey of the Availability of Intensity-Modulated Radiation Therapy and Stereotactic Radiosurgery in Canada

Radiation Oncology — Tue, 07 Feb 2012 05:00:00 +0100

Conclusions: The survey showed a growing adoption of IMRT and SRS in Canada, although the latter was available in less than half of responding centers. Barriers to implementation differed for IMRT compared to SRS. Enhancing human resources is an important consideration in the implementation of new RT technologies, due to the multidisciplinary nature of the planning and treatment process. (Source: Radiation Oncology)

Accelerated Partial Breast Irradiation Using Once-Daily Fractionation: Analysis of 312 Cases with Four Years Median Follow-Up

Radiation Oncology — Mon, 06 Feb 2012 05:00:00 +0100

Conclusions: External beam APBI with once daily fractionation has a low rate of IBF consistent with other published APBI studies. The ASTRO risk stratification did not differentiate a subset of patients with a higher rate of IBF. APBI may be an appropriate treatment for women with DCIS and ILC. (Source: Radiation Oncology)

Stereotactic body radiation therapy for liver tumours using flattening filter free beam: dosimetric and technical considerations.

Radiation Oncology — Wed, 01 Feb 2012 05:00:00 +0100

Purpose: To report the initial institute experience in terms of dosimetric and technical aspects in stereotactic body radiation therapy (SBRT) delivered using flattening filter free (FFF) beam in patients with liver lesions.Methods and Materials: From October 2010 to September 2011, 55 consecutive patients with 73 primary or metastatic hepatic lesions were treated with SBRT on TrueBeam using FFF beam and RapidArc technique. Clinical target volume (CTV) was defined on multi-phase CT scans, PET/CT, MRI, and 4D-CT. Dose prescription was 75Gy in 3 fractions to planning target volume (PTV). Constraints for organs at risk were: 700 cc of liver free from the 15Gy isodose, Dmax (Source: Radiation Oncology)

Narrow safety range of intraoperative rectal irradiation exposure volume for avoiding bleeding after seed implant brachytherapy

Radiation Oncology — Tue, 31 Jan 2012 05:00:00 +0100

Conclusion: By retrospective analysis exploring rV100 as intraoperative rectal dose-volume thresholds in 125I seed implant brachytherapy for prostate cancer, it is proved that rV100 should be less than 0.1 cc for preventing rectal bleeding. (Source: Radiation Oncology)

Use of combined maximum and minimum intensity projections to determine internal target volume in 4-dimensional CT scans for hepatic malignancies.

Radiation Oncology — Mon, 30 Jan 2012 05:00:00 +0100

Conclusion: The tool of ITV2M is recommended as a reliable method for generating ITVs from 4D CT data sets in liver cancer. (Source: Radiation Oncology)

Skin toxicity from external beam radiation therapy in breast cancer patients: protective effects of Resveratrol, Lycopene, Vitamin C and Anthocianin (Ixor(R))

Radiation Oncology — Mon, 30 Jan 2012 05:00:00 +0100

IntroductionThis is an observational study and the aim is to evaluate the effect of dietary supplements based on Resveratrol, Lycopene, Vitamin C and Anthocyanins (Ixor(R)) in reducing skin toxicity due to external beam radiotherapy in patients affected by breast cancer. Materials and Methods: 71 patients were enrolled and they were divided in two different groups: a control group (CG) of 41 patients treated with prophylactic topical therapy based on hyaluronic acid and topical steroid therapy in case of occurrence of radiodermatitis, and a Ixor-Group (IG) of 30 patients treated also with an oral therapy based on Resveratrol, Lycopene, Vitamin C and Anthocyanin (Ixor(R)) at a dose of 2 tablets/day, starting from 10 days before the radiation treatment until 10 days after the end of treatmen...

Pretreatment carcinoembryonic antigen level is a risk factor for para-aortic lymph node recurrence in addition to squamous cell carcinoma antigen following definitive concurrent chemoradiotherapy for squamous cell carcinoma of the uterine cervix

Radiation Oncology — Mon, 30 Jan 2012 05:00:00 +0100

Background: To identify pretreatment carcinoembryonic antigen (CEA) levels as a risk factor for para-aortic lymph node (PALN) recurrence following concurrent chemoradiotherapy (CCRT) for cervical cancer. Methods: From March 1995 to January 2008, 188 patients with squamous cell carcinoma (SCC) of the uterine cervix were analyzed retrospectively. No patient received PALN irradiation as the initial treatment. CEA and squamous cell carcinoma antigen (SCC-Ag) were measured before and after radiotherapy. PALN recurrence was detected by computer tomography (CT) scans. We analyzed the actuarial rates of PALN recurrence by using Kaplan-Meier curves. Multivariate analyses were carried out with Cox regression models. We stratified the risk groups based on the hazard ratios (HR). Results: Both pretrea...

Dose-escalation using intensity-modulated radiotherapy for prostate cancer - evaluation of quality of life with and without 18F-choline PET-CT detected simultaneous integrated boost

Radiation Oncology — Mon, 30 Jan 2012 05:00:00 +0100

Conclusions: Treatment planning with 18F-choline PET-CT allows a dose escalation to a macroscopic intraprostatic lesion without significantly increasing toxicity. (Source: Radiation Oncology)

Influence of secondary neutrons induced by proton radiotherapy for cancer patients with implantable cardioverter defibrillators

Radiation Oncology — Sun, 29 Jan 2012 05:00:00 +0100

Conclusions: With the present experimental settings, the probability was approximately 1 power-on reset per 50 Gy, which was below the dose level (60-80 Gy) generally used in proton radiotherapy. Further quantitative analysis in various settings is needed to establish guidelines regarding proton radiotherapy for cancer patients with ICDs. (Source: Radiation Oncology)

In vitro evaluation of photon and carbon ion radiotherapy in combination with chemotherapy in glioblastoma cells

Radiation Oncology — Fri, 27 Jan 2012 05:00:00 +0100

Conclusion: In conclusion, combination of carbon ion radiotherapy with chemotherapies of different mechanisms of action demonstrates additive effects. The most dominant effect was produced by paclitaxel, followed by camptothecin, as espected from previously published work. The present data serve as an important radiobiological basis for further combination experiments, as well as clinical studies on combination treatments. (Source: Radiation Oncology)

Repeated Radionuclide Therapy in Metastatic Paraganglioma Leading to the Highest Reported Cumulative Activity of 131I-MIBG

Radiation Oncology — Wed, 25 Jan 2012 05:00:00 +0100

We report the uneventful cumulative administration of 111 GBq (= 3 Ci) 131I-MIBG in a patient with metastatic paraganglioma. Ten courses of 131I-MIBG therapy were given within six years, accomplishing symptomatic, hormonal and tumour responses with no serious adverse effects. Chemotherapy with cisplatin/vinblastine/dacarbazine was the final treatment modality with temporary control of disease, but eventually the patient died of progression. The observed cumulative activity of 131I-MIBG represents the highest value reported to our knowledge, and even though 12.6 GBq of 90Y-DOTATOC were added intermediately, no associated relevant bone marrow, hepatic or other toxicity were observed. In an individual attempt to palliate metastatic disease high cumulative activity alone should not preclude th...

The impact of direct aperture optimization on plan quality and efficiency in complex head and neck IMRT

Radiation Oncology — Mon, 23 Jan 2012 05:00:00 +0100

Conclusions: All IMRT approaches implemented in the different treatment planning systems (TPS) generated clinically acceptable and comparable plans. No superior system in terms of PTV coverage and OAR sparing was found. Major differences in efficiency of the method in terms of calculated MU and treatment times were found. (Source: Radiation Oncology)

Administration of ON 01210.Na after exposure to ionizing radiation protects bone marrow cells by attenuating DNA damage response

Radiation Oncology — Fri, 20 Jan 2012 05:00:00 +0100

Conclusions: ON 01210.Na treatment significantly mitigated the hematopoietic toxicity induced by a sub-lethal radiation dose. Mechanistically, attenuation of ATM-p53 mediated DNA damage response by ON 01210.Na is contributing to the mitigation of radiation-induced hematopoietic toxicity. (Source: Radiation Oncology)

Interim-treatment Quantitative PET Parameters Predict Progression and Death Among Patients with Hodgkin's Disease

Radiation Oncology — Thu, 19 Jan 2012 05:00:00 +0100

Conclusions: Calculated PET metrics may provide predictive information beyond that of traditional clinical factors and may identify patients at high risk of treatment failure early for treatment intensification. (Source: Radiation Oncology)

Amelioration of radiation-induced skin injury by adenovirus mediated heme oxygenase-1 (HO-1) overexpression in rats

Radiation Oncology — Tue, 17 Jan 2012 05:00:00 +0100

Conclusions: The present study provides evidences for the protective role of HO-1 in alleviating radiation-induced skin damage in rats, which is helpful for the development of therapy for radiation-induced skin injury. (Source: Radiation Oncology)

A review of clinical trials of cetuximab combined with radiotherapy for non-small cell lung cancer

Radiation Oncology — Wed, 11 Jan 2012 05:00:00 +0100

Treatment of non-small cell lung cancer (NSCLC) is challenging in many ways. One of the problems is disappointing local control rates in larger volume disease. Moreover, the likelihood of both nodal and distant spread increases with primary tumour (T-) stage. Many patients are elderly and have considerable comorbidity. Therefore, aggressive combined modality treatment might be contraindicated or poorly tolerated. In many cases with larger tumour volume, sufficiently high radiation doses can not be administered because the tolerance of surrounding normal tissues must be respected. Under such circumstances, simultaneous administration of radiosensitizing agents, which increase tumour cell kill, might improve the therapeutic ratio. If such agents have a favourable toxicity profile, even elder...

Failure patterns and survival in patients with nasopharyngeal carcinoma treated with intensity modulated radiation in Northwest China: A pilot study

Radiation Oncology — Tue, 10 Jan 2012 05:00:00 +0100

Conclusions: IMRT with or without chemotherapy can improve the long term survival of NPC patients in Northwest ChinaDistant metastasis becomes the main cause of treatment failure. Age and anemia before radiotherapy were the main prognosis factors of NPC patients. (Source: Radiation Oncology)

Determination of Cell Survival after Irradiation via Clonogenic Assay versus Multiple MTT Assay - A Comparative Study

Radiation Oncology — Tue, 03 Jan 2012 05:00:00 +0100

For studying proliferation and determination of survival of cancer cells after irradiation, the multiple MTT assay, based on the reduction of a yellow water soluble tetrazolium salt to a purple water insoluble formazan dye by living cells was modified from a single-point towards a proliferation assay. This assay can be performed with a large number of samples in short time using multi-well-plates, assays can be performed semi-automatically with a microplate reader. Survival, the calculated parameter in this assay, is determined mathematically. Exponential growth in both control and irradiated groups was proven as the underlying basis of the applicability of the multiple MTT assay. The equivalence to a clonogenic survival assay with its disadvantages such as time consumption was proven in t...

PET/CT aids the staging of and radiotherapy planning for early-stage extranodal natural killer/T-cell lymphoma, nasal type: A case series.

Radiation Oncology — Fri, 30 Dec 2011 05:00:00 +0100

We describe three consecutive cases of localized ENKTL that presented to the Nova Scotia Cancer Centre in Halifax, Nova Scotia. All patients had a planning CT and MRI as well as a planning FDG-PET/CT in the radiotherapy treatment position, wearing immobilization masks. All patients received radiation alone. In two patients, PET/CT changed not only the stage, but also the target volume requiring treatment. The third patient was unable to tolerate an MRI, but was able to undergo PET/CT, which improved the accuracy of the target volume. PET/CT aided the staging of and radiotherapy planning for our patients and appears to be a promising tool in the treatment of ENKTL. (Source: Radiation Oncology)

Preliminary comparison of helical tomotherapy and mixed beams of unmodulated electrons and intensity modulated radiation therapy for treating superficial cancers of the parotid gland and nasal cavity

Radiation Oncology — Wed, 28 Dec 2011 05:00:00 +0100

Conclusions: Mixed beam treatments offer some dosimetric advantages over IMRT or helical tomotherapy for target depths that do not exceed the useful range of the electron beam. Adding a small IMRT component (e.g., IMRT:electron weighting = 1:4) to electron beam plans markedly improved target dose homogeneity and conformity for the cases examined in this study. (Source: Radiation Oncology)

Dose to level I and II axillary lymph nodes and lung by tangential field radiation in patients undergoing postmastectomy radiation with tissue expander reconstruction

Radiation Oncology — Wed, 28 Dec 2011 05:00:00 +0100

Conclusions: In patients undergoing PMRT with tissue expanders, incidental doses delivered by tangents to the axilla, as defined by the RTOG contouring atlas, do not provide adequate coverage. The posterior-superior region of level I and II is the region most commonly underdosed. Axillary volume coverage increased with increasing expander volumes in patients with bilateral reconstruction. Lung dose increased with increasing expander angle from midline. This information should be considered both when placing expanders and when designing PMRT tangent only treatment plans by contouring and targeting the axilla volume when axillary treatment is indicated. (Source: Radiation Oncology)

Initial investigation using statistical process control for quality control of accelerator beam steering

Radiation Oncology — Wed, 28 Dec 2011 05:00:00 +0100

Conclusion: Radiotherapy clinical efficiency and accelerator beam consistency may be improved by instituting SPC methods to monitor the beam steering process and detect abnormal changes prior to equipment failure. (Source: Radiation Oncology)

Population-based outcomes after whole brain radiotherapy and re-irradiation in patients with metastatic breast cancer in the trastuzumab era

Radiation Oncology — Wed, 28 Dec 2011 05:00:00 +0100

Conclusion: The proportion of cases with HER2 positive disease was increased at repeat BRT compared to initial BRT. RPA class 1 and 2 patients should be considered for repeat BRT. (Source: Radiation Oncology)

Radiotherapy and "new" drugs - new side effects?

Radiation Oncology — Wed, 21 Dec 2011 05:00:00 +0100

Conclusions: The addition of molecular targeted drugs to conventional radiotherapy outside of approved regimens or clinical trials warrants a careful consideration especially when used in conjunction in hypo-fractionated regimens. Clinical trials are urgently needed in order to address the open question in regard to efficacy, early and late toxicity. (Source: Radiation Oncology)

Risk factors of distant brain failure for patients with newly diagnosed brain metastases treated with stereotactic radiotherapy alone

Radiation Oncology — Mon, 19 Dec 2011 05:00:00 +0100

Conclusions: The patients with a score of 0-1 had a lower risk of DBF than the patients with higher scores did, and it may be reasonable to treat these patients with SRT alone and resort to whole-brain radiation therapy only for salvage. The patients with a score of 4 had the highest risk of developing DBF after stereotactic radiotherapy alone, these patients may be candidates for initial whole-brain radiation therapy or clinical trials. The patients with a score of 2-3 had a moderate risk of developing DBF, SRT alone combined with close clinical monitoring would be the optimal treatment regimen for such patients , and for those patients with difficulties in receiving close clinical mornitoring ,SRT combined with WBRT will be more suitable. (Source: Radiation Oncology)

Apoptosis induction and tumor cell repopulation: The yin and yang of radiotherapy

Radiation Oncology — Mon, 19 Dec 2011 05:00:00 +0100

The induction of tumor cell death is a central goal of radiotherapy. Surprisingly, a recent study sheds new light on this process, and the results presented by Huang et al. strongly question the benefit of radiation-induced apoptosis for the outcome of cancer radiotherapy. (Source: Radiation Oncology)

Spinal radiosurgery - efficacy and safety after prior conventional radiotherapy

Radiation Oncology — Fri, 16 Dec 2011 05:00:00 +0100

Conclusions: By applying spinal radiosurgery relevant radiation doses can be limited to small parts of the myelon. This prevents myelopathic side effects and makes it an effective and safe treatment option for well-suited patients. Especially for previously irradiated patients with local failure or pain salvage SRS represents a valuable treatment option with high local control rates, low toxicity and significant pain reduction. (Source: Radiation Oncology)

Can the risk of secondary cancer induction after breast conserving therapy be reduced using intraoperative radiotherapy (IORT) with low-energy x-rays?

Radiation Oncology — Fri, 16 Dec 2011 05:00:00 +0100

Conclusions: The calculations for maximal doses and volumes of OAR suggest that the risk of secondary cancer induction after IORT is lower than compared to APBI and EBRT. (Source: Radiation Oncology)

Theoretical analysis of the dose dependence of the oxygen enhancement ratio and its relevance for clinical applications

Radiation Oncology — Thu, 15 Dec 2011 05:00:00 +0100

Conclusions: The formalism presented in this paper can be used for various tissue and radiation types to estimate OER variations with dose and help to decide in clinical practice whether some dose changes in dose painting or in fractionation can bring more benefit in terms of the OER in the treatment of a specific hypoxic tumor. (Source: Radiation Oncology)

Clinical practice of image-guided spine radiosurgery - results from an international research consortium

Radiation Oncology — Thu, 15 Dec 2011 05:00:00 +0100

Conclusions: Results of this study reflect the current practice of spine radiosurgery in large academic centers. Despite close agreement was observed in many steps of spine radiosurgery, further research in form of retrospective and especially prospective studies is required to refine the details of spinal radiosurgery in terms of safety and efficacy. (Source: Radiation Oncology)

Fast IMRT by increasing the beam number and reducing the number of segments

Radiation Oncology — Fri, 09 Dec 2011 05:00:00 +0100

Conclusions: 2-Step Fast plans are suited to reduce the delivery time, especially if the data handling time per beam is short. The plan quality can be retained or even increased for fewer segments provided more gantry angles are used. (Source: Radiation Oncology)

Adjuvant or radical fractionated stereotactic radiotherapy for patients with pituitary functional and nonfunctional macroadenoma.

Radiation Oncology — Thu, 08 Dec 2011 05:00:00 +0100

Conclusions: SFRT is a safe and effective treatment for patients with PMA, although longer follow-up is needed to evaluate long-term outcomes. In this study, approximately 1 patient with visual field defect out of two had an improved visual function. (Source: Radiation Oncology)

Significance of Genomic Instability in Breast Cancer in Atomic Bomb Survivors: Analysis of Microarray-Comparative Genomic Hybridization

Radiation Oncology — Wed, 07 Dec 2011 05:00:00 +0100

Conclusions: Thus, archival FFPE tissues from A-bomb survivors are useful for genome-wide aCGH analysis. Our results suggested that A-bomb radiation may affect the increased amount of CNA as a hallmark of GIN and, subsequently, be associated with a higher histologic grade in breast cancer found in A-bomb survivors. (Source: Radiation Oncology)

Radiation techniques for acromegaly

Radiation Oncology — Fri, 02 Dec 2011 05:00:00 +0100

Radiotherapy (RT) remains an effective treatment in patients with acromegaly refractory to medical and/or surgical interventions, with durable tumor control and often biochemical remission; however, there are still concerns about its potential late toxicity, especially high rates of hypopituitarism. Stereotactic radiotherapy has been developed as a more accurate technique of irradiation with more precise tumour localization and consequently a reduction in the volume of normal tissue, particularly the brain, irradiated to high radiation doses. Radiation can be delivered in a single fraction by stereotactic radiosurgery (SRS) or as fractionated stereotactic radiotherapy (FSRT) in which smaller doses are delivered over 5-6 weeks in 25-30 treatments. A review of the recent literature suggests ...

First steps towards a fast-neutron therapy planning program

Radiation Oncology — Fri, 25 Nov 2011 05:00:00 +0100

Conclusions: In order to minimize the dose to healthy tissue, a conformal treatment is necessary. This can only be accomplished with the help of an advanced treatment planning system like the one developed here. Although all calculations were done for absorbed dose only, any biological dose weighting can be implemented easily, to take into account the increased radiobiological effectiveness of neutrons compared to photons. (Source: Radiation Oncology)

Endometrial cancer - reduce to the minimum. A new paradigm for adjuvant treatments?

Radiation Oncology — Fri, 25 Nov 2011 05:00:00 +0100

Conclusion: Recent data from randomised trials indicate that external beam radiation therapy - particularly in combination with extended lymph node dissection - or radical lymph node dissection increases toxicity without any improvement of overall survival rates. Thus, reduced surgical aggressiveness and limitation of radiotherapy to vaginal-vault-brachytherapy only is sufficient for most cases of early stage endometrial cancer. (Source: Radiation Oncology)

Significant impact of different oxygen breathing conditions on noninvasive in vivo tumor-hypoxia imaging using [18F]-fluoro-azomycinarabino-furanoside ([18F]FAZA)

Radiation Oncology — Fri, 25 Nov 2011 05:00:00 +0100

Background: [18F]FAZA is a PET biomarker with great potential for imaging tumor hypoxia. Aim of our study was to compare [18F]FAZA uptake in mice with subcutaneous exogenous CT26 colon carcinomas and endogenous polyoma middle-T (PyV-mT) mammary carcinomas and to analyze the influence of different breathing protocols in CT26 colon carcinomas as well as the reversibility or irreversibility of [18F]FAZA uptake. Methods: We injected subcutaneous CT26 colon carcinoma or polyomavirus middle-T (PyV-mT) mammary carcinoma-bearing mice intravenously with [18F]FAZA and performed PET scans 1-3 h post injection (p.i.). To analyze the impact of oxygen supply in CT26 carcinomas we used three different breathing protocols: (P0) air; (P1) 100 % oxygen 1 h prior injection until 3 h p.i.; (P2) 100 % oxygen b...

Long-term survival in patients with non-small cell lung cancer and synchronous brain metastasis treated with whole-brain radiotherapy and thoracic chemoradiation.

Radiation Oncology — Fri, 25 Nov 2011 05:00:00 +0100

Conclusions: Patients with NSCLC and brain metastasis might benefit from treatment with WBRT and concurrent thoracic chemoradiotherapy. The subgroup of N0-N1 patientsappears to achieve the greatest benefit. The result of this study warrants a prospective trial to confirm the benefit of this treatment. (Source: Radiation Oncology)

Induction chemotherapy with paclitaxel and cisplatin to concurrent radiotherapy and weekly paclitaxel in the treatment of loco-regionally advanced, stage IV (M0), head and neck squamous cell carcinoma. Mature results of a prospective study.

Radiation Oncology — Tue, 22 Nov 2011 05:00:00 +0100

Conclusions: This combined treatment was found to be feasible and active in advanced or unresectable, head and neck squamous cell carcinoma patients. Long-term results observed in this trial encourage to consider this approach in further investigation using newer radiation delivering technique and new molecularly agents. (Source: Radiation Oncology)

Genomic alterations in rectal tumors and response to neoadjuvant chemoradiotherapy: an exploratory study

Radiation Oncology — Fri, 18 Nov 2011 05:00:00 +0100

Conclusions: This exploratory study suggests that an in depth characterization of chromosomal alterations by aCGH would provide useful predictive information on response to neoadjuvant chemoradiotherapy and could help to optimize therapy in rectal cancer patients.The data discussed in this study are available on the NCBI Gene Expression Omnibus [GEO: GSE25885]. (Source: Radiation Oncology)

Albendazole sensitizes cancer cells to ionizing radiation

Radiation Oncology — Thu, 17 Nov 2011 05:00:00 +0100

Conclusions: Our study suggests that the orally available antihelminthic ABZ acts as a potent radiosensitizer in MM and SCLC cell lines. Further evaluation of ABZ in combination with radiation as a potential treatment for MM and SCLC brain metastases is warranted. (Source: Radiation Oncology)

Frameless linac-based stereotactic radiosurgery (SRS) for brain metastases: analysis of patient repositioning using a mask fixation system and clinical outcomes

Radiation Oncology — Wed, 16 Nov 2011 05:00:00 +0100

Conclusions: Frameless SRS is an effective treatment in the management of patients with brain metastases. The presented non-invasive mask-based fixation stereotactic system is associated with a high degree of patient repositioning accuracy; however, a careful evaluation is essential since occasional errors up to 3 mm may occur. (Source: Radiation Oncology)

Virtual 3D tumor marking - exact intraoperative coordinate mapping improve post-operative radiotherapy

Radiation Oncology — Wed, 16 Nov 2011 05:00:00 +0100

The quality of the interdisciplinary interface in oncological treatment between surgery, pathology and radiotherapy is mainly dependent on reliable anatomical three-dimensional (3D) allocation of specimen and their context sensitive interpretation which defines further treatment protocols. Computer-assisted preoperative planning (CAPP) allows for outlining macroscopical tumor size and margins. A new technique facilitates the 3D virtual marking and mapping of frozen sections and resection margins or important surgical intraoperative information. These data could be stored in DICOM format (Digital Imaging and Communication in Medicine) in terms of augmented reality and transferred to communicate patient's specific tumor information (invasion to vessels and nerves, non-resectable tumor) to on...

Peripheral doses in patients undergoing Cyberknife treatment for intracranial lesions. A single centre experience.

Radiation Oncology — Mon, 14 Nov 2011 05:00:00 +0100

Conclusion: Weighting the effect of the number of monitor units and the collimator size can be effectively used during the optimization procedure in order to choose the most suitable treatment plan that will deliver the maximum dose to the tumor, while being compatible with the dose constraints for the surrounding organs at risk. Attention is required in defining the thyroid gland as a structure of avoidance in the treatment plan especially in patients with benign diseases. (Source: Radiation Oncology)

Toxicity and cosmesis outcomes after single fraction partial breast irradiation in early stage breast cancer

Radiation Oncology — Fri, 11 Nov 2011 05:00:00 +0100

Conclusion: Our choice of a single dose of 21 Gy significantly increased the treatment related toxicity. However, this should not discourage novel SSPBI approaches with lower equivalent doses. (Source: Radiation Oncology)

Radioresistance of human glioma spheroids and expression of HSP70, p53 and EGFr

Radiation Oncology — Fri, 11 Nov 2011 05:00:00 +0100

Conclusions: These results indicate that the PI3K-Akt and MEK-ERK pathways triggered by EGFr confer GBM radioresistance. (Source: Radiation Oncology)

MiRNA expression patterns predict survival in glioblastoma

Radiation Oncology — Thu, 10 Nov 2011 05:00:00 +0100

Conclusions: At present, this is the first dataset defining a prognostic role of miRNA expression patterns in patients with glioblastoma. Having defined such a pattern, a prospective validation of this observation is required. (Source: Radiation Oncology)

Mixed modality treatment planning of Accelerated Partial Breast Irradiation: to improve complex dosimetry cases.

Radiation Oncology — Thu, 10 Nov 2011 05:00:00 +0100

Conclusions: The mixed technique showed a promising trend of reducing the volume of non-target breast tissue and heart exposure doses in APBI "complex cases". (Source: Radiation Oncology)

Volumetric modulated arc planning for lung stereotactic body radiotherapy using conventional and unflattened photon beams: a dosimetric comparison with 3D technique

Radiation Oncology — Wed, 09 Nov 2011 05:00:00 +0100

Conclusion: Besides the advantage of faster delivery times, VMAT plans demonstrated better conformity to target, sharper dose fall-off in normal tissues and lower dose to normal lung than the 3D plans for lung SBRT. More monitor units are often required for FFF-VMAT plans. (Source: Radiation Oncology)

Myocardial perfusion imaging with 99mTc - tetrofosmin SPECT in breast cancer patients that received postoperative radiotherapy: A case-control study

Radiation Oncology — Tue, 08 Nov 2011 05:00:00 +0100

Conclusion: The study suggests that radiation therapy to BC patients result in MPI abnormalities but without apparent clinical consequences. (Source: Radiation Oncology)

Impact of pathological tumor stage for salvage radiotherapy after radical prostatectomy in patients with prostate-specific antigen < 1.0 ng/ml

Radiation Oncology — Sat, 05 Nov 2011 04:00:00 +0100

Conclusions: In patients who have received salvage RT after RP with PSA < 1.0 ng/ml, pT stage and preoperative PSA were prognostic factors of bRFS. In particular, pT3-4 had a high risk for biochemical recurrence after salvage RT. (Source: Radiation Oncology)

Raster-scanned carbon ion therapy for malignant salivary gland tumors: acute toxicity and initial treatment response

Radiation Oncology — Wed, 02 Nov 2011 04:00:00 +0100

Conclusion: Acute toxicity remains low in IMRT with carbon ion boost also in R1-resected patients and patients undergoing re-irradiation. R2-resected patients showed high rates of treatment response, though follow-up is too short to assess long-term disease control. (Source: Radiation Oncology)

Bilateral kidney preservation by volumetric-modulated arc therapy (RapidArc) compared to conventional radiation therapy (3D-CRT) in pancreatic and bile duct malignancies

Radiation Oncology — Mon, 31 Oct 2011 04:00:00 +0100

Conclusion: RapidArc allows significant dose reduction, in particular for homolateral kidney and bowel, while maintaining target coverage. This would have a promising impact on reducing toxicities. (Source: Radiation Oncology)

MVP and Vaults: a role in the radiation response

Radiation Oncology — Mon, 31 Oct 2011 04:00:00 +0100

Vaults are evolutionary highly conserved ribonucleoproteins particles with a hollow barrel-like structure. The main component of vaults represents the 110 kDa major vault protein (MVP), whereas two minor vaults proteins comprise the 193 kDa vault poly(ADP-ribose) polymerase (vPARP) and the 240 kDa telomerase-associated protein-1 (TEP-1). Additionally, at least one small and untranslated RNA is found as a constitutive component. MVP seems to play an important role in the development of multidrug resistance. This particle has also been implicated in the regulation of several cellular processes including transport mechanisms, signal transmission and immune responses. Vaults are considered a prognostic marker for different cancer types. The level of MVP expression predicts the clinical outcome...

Acute toxicity in prostate cancer patients treated with and without image-guided radiotherapy

Radiation Oncology — Fri, 28 Oct 2011 04:00:00 +0100

Conclusions: In this study, prostate cancer patients treated radically with IGRT had less severe urinary frequency, diarrhoea and fatigue during treatment compared to patients treated with non-IGRT. Onset of these symptoms was earlier in the non-IGRT group. IGRT results in less acute toxicity during radiotherapy in prostate cancer. (Source: Radiation Oncology)

Dosimetric and motion analysis of margin-intensive therapy by stereotactic ablative radiotherapy for resectable pancreatic cancer

Radiation Oncology — Fri, 28 Oct 2011 04:00:00 +0100

Conclusions: AC does not significantly reduce the limited motion of structures in close proximity to the MIT target and does not significantly increase the dose to OARs that can be displaced by the compression plate. The treatment planning techniques evaluated in this study have different advantages with no clearly superior method in our analysis. Dose to adjacent vessels may be reduced with 3DSABR or IMRT techniques, while conformality is increased with IMRT or CK. (Source: Radiation Oncology)

Spinal cord stimulators and radiotherapy: First case report and practice guidelines

Radiation Oncology — Tue, 25 Oct 2011 04:00:00 +0100

Spinal cord stimulators (SCS) are a well-recognised treatment modality in the management of a number of chronic neuropathic pain conditions, particularly failed back syndrome and radiculopathies. The implantable pulse generator (IPG) component of the SCS is designed and operates in a similar fashion to that of a cardiac pacemaker. The IPG consists of an electrical generator, lithium battery, transmitter/receiver and a minicomputer. When stimulated, it generates pulsed electrical signals which stimulate the dorsal columns of the spinal cord, thus alleviating pain. Analogous to a cardiac pacemaker, it can be potentially damaged by ionising radiation from a linear accelerator, in patients undergoing radiotherapy. Herein we report our clinical management of the first reported case of a patient...

Total error shift patterns for daily CT on rails image-guided radiotherapy to the prostate bed

Radiation Oncology — Mon, 24 Oct 2011 04:00:00 +0100

Conclusions: The overall daily total error shift pattern for these 17 patients simulated with an empty bladder, and treated with CT on rails IGRT was predominantly systematic. Despite this, the temporal vector trends showed complex behaviors and unpredictable changes in magnitude and direction. These findings highlight the importance of using daily IGRT in post-prostatectomy patients. (Source: Radiation Oncology)

Planning analysis for locally advanced lung cancer: dosimetric and efficiency comparisons between intensity-modulated radiotherapy (IMRT), single-arc/partial-arc volumetric modulated arc therapy (SA/PA-VMAT)

Radiation Oncology — Fri, 21 Oct 2011 04:00:00 +0100

Purpose: To analyze the differences between the intensity-modulated radiotherapy (IMRT), single/partial-arc volumetric modulated arc therapy (SA/PA-VMAT) techniques in treatment planning for locally advanced lung cancer.Methods and materials: 12 patients were retrospectively studied. In each patient's case, several parameters were analyzed based on the dose-volume histograms (DVH) of the IMRT, SA/PA-VMAT plans respectively. Also, each plan was delivered to a phantom for time comparison. Results: The SA-VMAT plans showed the superior target dose coverage, although the minimum/mean/maximum doses to the target were similar. For the total and contralateral lungs, the higher V5/10, lower V20/30 and mean lung dose (MLD) were observed in the SA/PA-VMAT plans (p (Source: Radiation Oncology)

Toxicity after radiochemotherapy for glioblastoma using Temozolomide - a retrospective evaluation

Radiation Oncology — Fri, 21 Oct 2011 04:00:00 +0100

Conclusion: Our survival data were well within the range taken from the literature. However, we noticed a considerable frequency and intensity of side effects to bone marrow and liver. These lead to the recommendations that regular examinations of blood cell count and liver enzymes should be performed during therapy and temozolomide should not be applied or application should be terminated according to the criteria given by the manufacturer. (Source: Radiation Oncology)

Clinical application of CT-guided 125I seed interstitial implantation for local recurrent rectal carcinoma

Radiation Oncology — Tue, 18 Oct 2011 04:00:00 +0100

Conclusion: CT-guided 125I seed implantation appeared to be a safe, useful and less complicated interventional treatment option for local recurrent rectal carcinoma . (Source: Radiation Oncology)

Survival of tumor cells after proton irradiation with ultra-high dose rates

Radiation Oncology — Tue, 18 Oct 2011 04:00:00 +0100

Conclusions: At the dose rates investigated here, which are expected to correspond to those in radiation therapy using laser-driven particles, the RBE of the pulsed and the (conventional) continuous irradiation mode do not differ significantly. (Source: Radiation Oncology)

Rib fracture after stereotactic radiotherapy on follow-up thin-section computed tomography in 177 primary lung cancer patients

Radiation Oncology — Thu, 13 Oct 2011 04:00:00 +0100

Conclusion: Rib fracture is frequently seen after SRT for lung cancer on CT, and is often associated with chest wall edema, thinning of the cortex and osteosclerosis. However, related chest wall pain is less frequent and is generally mild if present. (Source: Radiation Oncology)

GP96 is over-expressed in oral cavity cancer and is a poor prognostic indicator for patients receiving radiotherapy

Radiation Oncology — Wed, 12 Oct 2011 04:00:00 +0100

Conclusion: GP96 may play roles in radioresistance which attributes to tumor invasiveness in oral cancer patients receiving radiotherapy. GP96 may serve as a novel prognostic marker of radiotherapy. However, further independent studies are required to validate our findings in a larger series. (Source: Radiation Oncology)

Liposomal doxorubicin improves radiotherapy response in hypoxic prostate cancer xenografts

Radiation Oncology — Fri, 07 Oct 2011 04:00:00 +0100

Conclusions: We found that DXR encapsulated in liposomes improved the therapeutic effect of RT under hypoxic conditions without affecting vascular functions. Thus, we propose that for cytotoxic agents affecting tumor vascular functions liposomes may be a promising drug delivery technology for use in chemoradiotherapy. (Source: Radiation Oncology)

The prognostic value of the nodal ratio in N1 breast cancer

Radiation Oncology — Thu, 06 Oct 2011 04:00:00 +0100

Conclusions: A NR >0.15 was associated with an increased risk of recurrence, especially in young patients with unfavorable pathologic profiles. (Source: Radiation Oncology)

Targeting alphavbeta3 and alphavbeta5 inhibits photon-induced hypermigration of malignant glioma cells

Radiation Oncology — Thu, 06 Oct 2011 04:00:00 +0100

Conclusions: Peripheral glioma cells are at risk of attraction into the adjacent healthy brain by serum components leaking through the blood brain barrier (BBB). Radiation therapy is associated with upregulation of Vn receptor integrins and enhanced glioma cell migration at sublethal doses. This effect can be inhibited by specific integrin blockade. Future therapeutical benefit may be derived from pharmacological integrin inhibition in combination with photon irradiation. (Source: Radiation Oncology)

Mitochondrial DNA alterations of peripheral lymphocytes in acute lymphoblastic leukemia patients undergoing total body irradiation therapy

Radiation Oncology — Thu, 06 Oct 2011 04:00:00 +0100

Conclusions: mtDNA and CD content may be considered as predictive factors to radiation toxicity. (Source: Radiation Oncology)

Intensity-Modulated Radiotherapy for Squamous Cell Carcinoma of the Anal Canal: Efficacy of a Low Daily Dose to Clinically Negative Regions

Radiation Oncology — Thu, 06 Oct 2011 04:00:00 +0100

Conclusions: Our data support using doses between 1.50 and 1.80 Gy/day to clinically uninvolved regions. (Source: Radiation Oncology)

Incidence of seed migration to the chest, abdomen, and pelvis after transperineal interstitial prostate brachytherapy with loose 125I seeds

Radiation Oncology — Wed, 05 Oct 2011 04:00:00 +0100

Conclusion: We showed the incidence of seed migration to the chest, abdomen and pelvis. Seed migration did not have a significant effect on postimplant prostate D90. (Source: Radiation Oncology)

Radiation Induced Temporal Lobe Necrosis in Patients with Nasopharyngeal Carcinoma: a Review of New Avenues in Its Management

Radiation Oncology — Fri, 30 Sep 2011 04:00:00 +0100

Temporal lobe necrosis (TLN) is the most debilitating late-stage complication after radiation therapy in patients with nasopharyngeal cancer (NPC). The bilateral temporal lobes are inevitably encompassed in the radiation field and are thus prone to radiation induced necrosis. The wide use of 3D conformal and intensity-modulated radiation therapy (IMRT) in the treatment of NPC has led to a dwindling incidence of TLN. Yet, it still holds great significance due to its incapacitating feature and the difficulties faced clinically and radiologically in distinguishing it from a malignancy. In this review, we highlight the evolution of different imaging modalities and therapeutic options. FDG PET, SPECT and Magnetic Spectroscopy are among the latest imaging tools that have been considered. In term...

Commissioning and early experience with a new-generation low-energy linear accelerator with advanced delivery and imaging functionalities.

Radiation Oncology — Fri, 30 Sep 2011 04:00:00 +0100

Background: A new-generation low-energy linear accelerator (UNIQUE) was introduced in the clinical arena during 2009 by Varian Medical Systems. The world's first UNIQUE was installed at Oncology Institute of Southern Switzerland and put into clinical operation in June 2010. The aim of the present contribution was to report experience about its commissioning and first year results from clinical operation. Methods: Commissioning data, beam characteristics and the modeling into the treatment planning system were summarized. Imaging system of UNIQUE included a 2D-2D matching capability and tests were performed to identify system repositioning capability. Finally, since the system is capable of delivering volumetric modulated arc therapy with RapidArc, a summary of the tests performed for such ...

Postoperative Chemoradiation for Resected Gastric Cancer - Is the MacDonald Regimen Tolerable? A Retrospective Multi-Institutional Study

Radiation Oncology — Thu, 29 Sep 2011 04:00:00 +0100

Conclusions: In our experience, postoperative chemoradiation as per Intergroup-0116 seems to be substantially toxic, with a mortality rate which seems higher than reported in that trial. Efficacy data appears comparable to the original report. Following postoperative chemoradiation, involvement of surgical margins still has a detrimental impact on patient outcome. (Source: Radiation Oncology)

Evaluation of adjuvant chemoradiation therapy for ampullary adenocarcinoma: the Johns Hopkins Hospital - Mayo Clinic collaborative study

Radiation Oncology — Wed, 28 Sep 2011 04:00:00 +0100

Background: The role of adjuvant chemoradiation therapy for ampullary carcinoma is unknown. Previous literature suggests that certain populations with high risk factors for recurrence may benefit from adjuvant chemoradiation. We combined the experience of two institutions to better delineate which patients may benefit from adjuvant chemoradiation. Methods: Patients who underwent curative surgery for ampullary carcinoma at the Johns Hopkins Hospital (n=290; 1992-2007) and at the Mayo Clinic (n=130; 1977-2005) were reviewed. Patients with (Source: Radiation Oncology)

Parotid gland-recovery after radiotherapy in the head and neck region: 36 months follow-up of a prospective clinical study

Radiation Oncology — Tue, 27 Sep 2011 04:00:00 +0100

Background: The aim of the present study was to evaluate the recovery potential of the parotid glands after using either 3D-conformal-radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) by sparing one single parotid gland. Methods: Between 06/2002 and 10/2008, 117 patients with head and neck cancer were included in this prospective, non-randomised clinical study. All patients were treated with curative intent. Salivary gland function was assessed by measuring stimulated salivary flow at the beginning, during and at the end of radiotherapy as well as 1, 6, 12, 24, and 36 months after treatment. Measurements were converted to flow rates and normalized relative to rates before treatment. Mean doses (Dmean) were calculated from dose-volume histograms based on computed tomographies...

Docetaxel- and 5-FU-concurrent radiotherapy in patients presenting unresectable locally advanced pancreatic cancer: a FNCLCC-ACCORD/0201 randomized phase II trial's pre-planned analysis and case report of a 5.5-year disease-free survival.

Radiation Oncology — Mon, 26 Sep 2011 04:00:00 +0100

Conclusions: Combination of 5-FU, docetaxel and radiotherapy has inadequate efficacy in the treatment of LAPC despite good tolerance for the 5-FU-DCT regimen.Trial registration: Current Controlled Trials NCT00112697 (Source: Radiation Oncology)

Inter-observer variability in contouring the penile bulb on CT images for prostate cancer treatment planning

Radiation Oncology — Sat, 24 Sep 2011 04:00:00 +0100

Several investigations have recently suggested the existence of a correlation between the dose received by the penile bulb (PB) and the risk of erectile dysfunction (ED) after radical radiotherapy for clinically localized prostate carcinoma.A prospective multi-Institute study (DUE-01) was implemented with the aim to assess the predictive parameters of ED. Previously, an evaluation of inter-observer variations of PB contouring was mandatory in order to quantify its impact on PB dose-volume parameters by means of a dummy run exercise.Fifteen observers, from different Institutes, drew the PB on the planning CT images of ten patients; inter-observer variations were analysed in terms of PB volume variation and cranial/caudal limits. 3DCRT treatment plans were simulated to evaluate the impact of...

Evaluation of Early Imaging Response Criteria in Glioblastoma Multiforme

Radiation Oncology — Fri, 23 Sep 2011 04:00:00 +0100

Conclusions: We show that while a subjective interpretation of early radiological progression from baseline is generally associated with poor outcome, true progressors cannot be distinguished from pseudoprogressors. In contrast, the magnitude of early imaging volumetric response may be a predictive and quantitative metric of favorable outcome. (Source: Radiation Oncology)

Disease control and functional outcome in three modern combined organ preserving regimens for locally advanced squamous cell carcinoma of the head and neck (SCCHN)

Radiation Oncology — Fri, 23 Sep 2011 04:00:00 +0100

Conclusion: Late radiation effects in our cohort are rare. No significant differences in outcome between RChT and RIT were observed. Adding TPF suggests improved progression-free and overall survival, impact of TPF on locoregional PFS was marginal, therefore radiotherapeutic options for intensification of local treatment should be explored. (Source: Radiation Oncology)

Impact of tumor volume and systemic therapy on outcome in patients undergoing IMRT for large volume head neck cancer

Radiation Oncology — Thu, 22 Sep 2011 04:00:00 +0100

Conclusion: Patients with tGTV >70cc unable to undergo any systemic therapy represented a subgroup in which disease control was achievable in ~130cc fails to meet its curative aim. (Source: Radiation Oncology)

Combination of suberoylanilide hydroxamic acid with heavy ion therapy shows promising effects in infantile sarcoma cell lines

Radiation Oncology — Tue, 20 Sep 2011 04:00:00 +0100

Conclusion: Our in vitro data suggest an increase of the therapeutic ratio by the combination of SAHA with HIT in infantile sarcoma cell lines. (Source: Radiation Oncology)

Delineation in thoracic oncology: a prospective study of the effect of training on contour variability and dosimetric consequences.

Radiation Oncology — Mon, 19 Sep 2011 04:00:00 +0100

Conclusion: There were no significant differences for the delineation of the GTV and CTV before and after the course, although the differences tended to decrease after the course. The good initial quality of the contours could explain the lack of difference. V20 for lung was higher in the residents group compared to the experts group (23.2% vs 36.5%). No other treatment planning consequences were observed for other critical organs. (Source: Radiation Oncology)

Prior surgical intervention and tumor size impact clinical outcome after precision radiotherapy for the treatment of optic nerve sheath meningiomas (ONSM)

Radiation Oncology — Sun, 18 Sep 2011 04:00:00 +0100

Conclusion: Long-term outcome after FSRT for ONSM shows improved vision in patients not treated surgically prior to RT; moreover, the best improvement of visual deficits are observed in patients with larger target volumes. The absence of tumor occurrences supports that FSRT is a strong alternative to surgical resection especially in small tumors without extensive compression of normal tissue structures (Source: Radiation Oncology)

In vitro characterization of cells derived from chordoma cell line U-CH1 following treatment with X-rays, heavy ions and chemotherapeutic drugs

Radiation Oncology — Wed, 14 Sep 2011 04:00:00 +0100

Conclusion: Our data provide the first comprehensive cellular characterization using cells of chordoma origin and furnish the biological basis for successful clinical results of chordoma treatment by heavy ions. (Source: Radiation Oncology)

Prognostic significance of IDH-1 and MGMT in patients with glioblastoma: One step forward, and one step back?

Radiation Oncology — Tue, 13 Sep 2011 04:00:00 +0100

A group of 160 patients with primary glioblastoma treated with radiotherapy and temozolomide was analyzed for the impact of O6-methyl-guanyl-methyl-transferase (MGMT)-promoter methylation as well as isocitrate dehydrogenase (IDH)1-mutational status. Unexpectedly, overall survival or progression-free survival were not longer in the group with methylated MGMT-promoter as compared to patients without that methylation. IDH-1 mutations were significantly associated with increased overall survival. (Source: Radiation Oncology)

Phospho-ERK and AKT status, but not KRAS mutation status, are associated with outcomes in rectal cancer treated with chemoradiotherapy

Radiation Oncology — Mon, 12 Sep 2011 04:00:00 +0100

Conclusions: KRAS mutation was not associated with lesser response to chemoradiotherapy or worse OS. High p-ERK expression was associated with better OS and response. Higher p-AKT expression was correlated with better response but not OS. (Source: Radiation Oncology)

Feasibility and early clinical assessment of Flattening Filter Free (FFF) based Stereotactic Body Radiotherapy (SBRT)treatments

Radiation Oncology — Mon, 12 Sep 2011 04:00:00 +0100

Conclusions: This study showed that, with respect to acute toxicity, SBRT with FFF beams showed to be a feasible technique in 70 consecutive patients with various primary and metastatic lesions in the body. (Source: Radiation Oncology)

Technology Assessment of Automated Atlas Based Segmentation in Prostate Bed Contouring

Radiation Oncology — Fri, 09 Sep 2011 04:00:00 +0100

Conclusion: The AABS tool results in a time savings, and when used to generate auto-contours for the femoral heads, bladder and rectum had superior to good spatial overlap. However, the generated auto-contours for the prostate bed and penile bulb need improvement. (Source: Radiation Oncology)

Increased betulinic acid induced cytotoxicity and radiosensitivity in glioma cells under hypoxic conditions

Radiation Oncology — Fri, 09 Sep 2011 04:00:00 +0100

Conclusion: Our results suggest that BA is capable of improving the effects of tumor therapy in human malignant glioma cells, particularly under hypoxic conditions. Further investigations are necessary to characterize its potential as a radiosensitizer. (Source: Radiation Oncology)

Toxicity report of once weekly radiation therapy for low-risk prostate adenocarcinoma: preliminary results of a phase I/II trial

Radiation Oncology — Fri, 09 Sep 2011 04:00:00 +0100

We report the toxicity profile of such treatment.Materials and MethodsWe conducted a multi-institution phase I/II trial of three-dimensional conformal radiation therapy (3D-CRT) for favourable-risk prostate cancer (T1a-T2a, Gleason [less than or equal to] 6 and PSA < 10). RT consisted of 45 Gy in nine 5 Gy fractions, once weekly. Primary end-points were feasibility and late gastrointestinal (GI) toxicity (RTOG scale), while secondary end-points included acute GI toxicity, acute and late genitourinary (GU) toxicity, biochemical control, and survival. Results: Between 2006 and 2008, 80 patients were treated. No treatment interruptions occurred. The median follow-up is 33 months (range: 20-51). Maximal grade 1, 2, and 3 acute ( (Source: Radiation Oncology)

Assessment of peri- and postoperative complications and Karnofsky-performance status in head and neck cancer patients after radiation or chemoradiation that underwent surgery with regional or free-flap reconstruction for salvage , palliation, or to improve function

Radiation Oncology — Mon, 05 Sep 2011 23:00:00 +0100

Conclusions: We conclude that within this (chemo)radiated patient population surgical interventions for salvage, palliation or improve function can be safely performed once vascularised grafts are used. (Source: Radiation Oncology)

DNA double-strand break induction in Ku80-deficient CHO cells following Boron Neutron Capture Reaction

Radiation Oncology — Sun, 04 Sep 2011 23:00:00 +0100

Conclusion: Mutant xrs-5 cells show extreme sensitivity to ionizing radiation, because xrs-5 cells lack functional Ku-protein. Our results suggest that the DNA-DSBs induced by BNCR were not well repaired in the Ku80 deficient cells. The RBE following BNCR of radio-sensitive mutant cells was not increased but was lower than that of radio-resistant cells. These results suggest that gamma-ray resistant cells have an advantage over gamma-ray sensitive cells in BNCR. (Source: Radiation Oncology)

In Vivo Assessment of Catheter Positioning Accuracy and Prolonged Irradiation Time on Liver Tolerance Dose after Single-Fraction 192-Ir High-Dose-Rate Brachytherapy

Radiation Oncology — Sun, 04 Sep 2011 23:00:00 +0100

Conclusions: Positioning accuracy of brachytherapy catheters is sufficient for clinical practice. Reduced tolerance dose in areas exposed to prolonged irradiation is contradictory to results published in the current literature. Effects of prolonged dose administration on the liver tolerance dose for treatment times of up to 60 minutes per HDR-BT session are not pronounced compared to effects of positioning accuracy of the brachytherapy catheters and are therefore of minor importance in treatment planning. (Source: Radiation Oncology)

Volumetric modulated arc therapy is superior to conventional intensity modulated radiotherapy - a comparison among prostate cancer patients treated in an Australian centre.

Radiation Oncology — Sun, 04 Sep 2011 23:00:00 +0100

This study is an audit of the RA experience in an Australian department with a planning and economic comparison to IM. Methods: 30 consecutive prostate cancer patients treated radically with RA were analyzed. Eight RA patients treated definitively were then completely re-planned with 3D conformal radiotherapy (3D); and a conventional sliding window IM technique; and a new RA plan. The acceptable plans and their treatment times were compared and analyzed for any significant difference. Differences in staff costs of treatment were computed and analyzed. Results: Thirty patients had been treated to date with eight being treated definitely to at least 74 Gy, nine post high dose brachytherapy (HDR) to 50.4Gy and 13 post prostatectomy to at least 64Gy. All radiotherapy courses were completed wit...

Neoadjuvant capecitabine, radiotherapy, and bevacizumab (CRAB) in locally advanced rectal cancer: results of an open-label phase II study

Radiation Oncology — Tue, 30 Aug 2011 23:00:00 +0100

Conclusions: This study demonstrates the feasibility of preoperative chemoradiotherapy with bevacizumab and capecitabine. The observed adverse events of neoadjuvant treatment are comparable with those previously reported, but the pCR rate was lower. (Source: Radiation Oncology)

Helical tomotherapy in the treatment of pediatric malignancies: a preliminary report of feasibility and acute toxicity

Radiation Oncology — Thu, 25 Aug 2011 23:00:00 +0100

Conclusion: HT in pediatric population is feasible and safe treatment modality. It is characterized by an acceptable level of acute toxicity that we have seen in this highly selected pediatric patient cohort with clinical features of poor prognosis and/or aggressive therapy needed. Despite of a dosimetrical advantage of HT technique, an exhaustive analysis of long-term follow-up data is needed to assess late toxicity, especially in this potentially sensitive to radiation population. (Source: Radiation Oncology)

On the dosimetric impact of inhomogeneity management in the Acuros XB algorithm for breast treatment

Radiation Oncology — Thu, 25 Aug 2011 23:00:00 +0100

Conclusions: Acuros XB, differently from AAA, is capable to distinguish between the different elemental compositions of the body, and suggests the possibility to further improve the accuracy of the dose plans computed for actual treatment of patients. (Source: Radiation Oncology)

Prognosticators and Risk Grouping in Patients with Lung Metastasis from Nasopharyngeal Carcinoma: A More Accurate and Appropriate Assessment of Prognosis

Radiation Oncology — Thu, 25 Aug 2011 23:00:00 +0100

Background: Lung metastases arising from nasopharyngeal carcinomas (NPC) have a relatively favourable prognosis. The purpose of this study was to identify the prognostic factors and to establish a risk grouping in patients with lung metastases from NPC. Methods: A total of 198 patients who developed lung metastases from NPC after primary therapy were retrospectively recruited from January 1982 to December 2000. Univariate and multivariate analyses of clinical variables were performed using Cox proportional hazards regression models. Actuarial survival rates were plotted against time using the Kaplan-Meier method, and log-rank testing was used to compare the differences between the curves. Results: The median overall survival (OS) period and the lung metastasis survival (LMS) period were 51...

Upfront systemic chemotherapy and preoperative short-course radiotherapy with delayed surgery for locally advanced rectal cancer with distant metastases

Radiation Oncology — Tue, 23 Aug 2011 23:00:00 +0100

Conclusions: Upfront chemotherapy and short course RT with delayed surgery is a valuable alternative treatment approach for patients with MRF involvement or closeness of rectal cancer with distant metastases. (Source: Radiation Oncology)

Effects of radiation therapy on tissue and serum concentrations of tumour associated trypsin inhibitor and their prognostic significance in rectal cancer patients

Radiation Oncology — Tue, 23 Aug 2011 23:00:00 +0100

Conclusions: The results presented here further validate the utility of t-TATI and s-TATI as prognostic biomarkers in patients with rectal cancer, independent of neoadjuvant RT. (Source: Radiation Oncology)

Impact of the frequency of online verifications on the patient set-up accuracy and set-up margins

Radiation Oncology — Tue, 23 Aug 2011 23:00:00 +0100

Conclusion: In patients where high set-up accuracy is desired, daily online verification is highly recommended. (Source: Radiation Oncology)

Reirradiation of Head and Neck Cancer Focusing on Hypofractionated Stereotactic Body Radiation Therapy

Radiation Oncology — Sat, 20 Aug 2011 23:00:00 +0100

Reirradiation is a feasible option for patients who do not otherwise have treatment options available. Depending on the location and extent of the tumor, reirradiation may be accomplished with external beam radiotherapy, brachytherapy, radiosurgery, or intensity modulated radiation therapy (IMRT). Although there has been limited experience with hypofractionated stereotactic radiotherapy (hSRT), it may have the potential for curative or palliative treatment due to its advanced precision technology, particularly for limited small lesion. On the other hand, severe late adverse reactions are anticipated with reirradiation than with initial radiation therapy. The risk of severe late complications has been reported to be 20- 40% and is related to prior radiotherapy dose, primary site, retreatmen...

Guidelines for delineation of lymphatic clinical target volumes for high conformal radiotherapy: head and neck region.

Radiation Oncology — Thu, 18 Aug 2011 23:00:00 +0100

The success of radiotherapy depends on the accurately delineation of the cxlinical target volume. The delineation of the lymph node regions has most impact especially for tumors in the head and neck region. The purpose of this article was the development of an atlas for the delineation of the clinical target volume for patients, who should receive radiotherapy for a tumor of the head and neck region. Literature was reviewed for localisations of the adjacent lymph node regions and their lymph drain in dependence of the tumor entity. On this basis the lymph node regions were contoured on transversal CT slices. The probability for involvement was reviewed and a recommendation for the delineation of the CTV was generated. (Source: Radiation Oncology)

Mechanisms of increased risk of tumorigenesis in Atm and Brca1 double heterozygosity

Radiation Oncology — Tue, 16 Aug 2011 23:00:00 +0100

Conclusions: The quantity of critical proteins such as ATM and BRCA1 plays an important role in determination of the fate of cells exposed to ionizing radiation and double heterozygosity increases the risk of tumorigenesis. These findings also benefit understanding of the individual susceptibility to tumor initiation. (Source: Radiation Oncology)

Concurrent Image-guided Intensity Modulated Radiotherapy and Chemotherapy Following Neoadjuvant Chemotherapy for Locally Advanced Nasopharyngeal Carcinoma

Radiation Oncology — Fri, 12 Aug 2011 23:00:00 +0100