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Abstract: Purpose: At the request of the French nuclear safety authority (Autorité de Sûreté Nucléaire, ASN) a working party of multidisciplinary experts was initiated to elaborate a report regarding propositions for the clinical practice of stereotactic radiation therapy and the related medical physics. Material and methods: Several stereotactic radiation therapy experts were audited by the working party, especially neurosurgeons and neuroradiologists, as well as radiation oncologists, medical physicists and radiation technologists. An international survey was conducted looking at legal requirements and guidelines concerning stereotactic radiation therapy. A national survey was conducted in France among 29 departments performing stereotactic radiation therapy. The working party report was submitted for advice to the permanent group of medical experts of ASN. Results: Among the 13 countries who responded, very few have legal documents. Some of them are stating that stereotactic radiation therapy must be performed in a radiotherapy department and only by well-trained professionals. Guidelines describing the role of each participant have been published in the USA. In France, stereotactic radiation therapy is performed with dedicated machines or adapted linear accelerators. In 2009, within the 29 departments, 4247 patients were treated with stereotactic radiation therapy representing 4% of the patients treated with external beam radiation therapy. Intracranial lesions were: 3383 and extracranial: 864. The working party of multidisciplinary experts made 7 recommendations. The first one saying that stereotactic radiation therapy must be considered as a radiotherapy. The permanent group of medical experts is asking to modify the “décret du 19 mars 2007” regarding “radiosurgery”. Conclusion: The medical benefit of stereotactic radiation therapy is well admitted and it is an increasingly used technique. This work through practical guidelines and legal propositions intends to promote a well-controlled development of this radiotherapy technique. [Copyright &y& Elsevier]

Abstract: Purpose: To evaluate the accuracy of patient repositioning in fractionated cerebral stereotactic radiotherapy using a Brain Lab™ stereotactic cranial mask in conjunction with standard dental fixation. Patients and methods: Fifty planning and checking CT scans were performed in 25 patients. The check CT scan was performed before or after one of the three sessions of treatment. Coregistration to the planning CT scan was used to assess alignment of the isocentre to the reference markers. The relative position of the PTV with regard to isocentre allowed us to determine its total displacement (3D vector). Results: Mean isocentre translations (±SD) taking into account direction were −0.01±0.7, −0.2±1.3 and 0.07±0.5mm in mediolateral, craniocaudal and anteroposterior directions respectively. Mean rotations (± SD) were −0.02±0.6, −0.08±0.3 and −0.1±0.3 degree in mediolateral, craniocaudal and anteroposterior axes respectively. Mean overall PTV displacement was 1.8±1.5mm. PTV displacement was smaller than 2 and 3mm in 19/25 and 23/25 patients respectively. Conclusion: The accuracy of patient positioning using a stereotactic cranial mask system is similar to those reported in the literature and shows a satisfactory reproducibility with a standard dental fixation. [Copyright &y& Elsevier]

Abstract: Purpose: To analyze the prognostic factors of loco regional control (LRC), specific survival (SS) and sphincter conservation (SC) of patients treated by curative and conservative irradiation for an epidermoid cancer of anal canal in our institution. Patients and methods: From 1976 to 2005, 286 patients (pts) were treated by exclusive radiotherapy (180 pts) or chemo-radiotherapy (106 pts) followed by a brachytherapy boost (233 pts) or external beam radiotherapy boost (24 pts). Forty-three pts were stage I, 154 stage II, 31 stage IIIA and 53 stage IIIB. Results: The mean follow-up was 65 months (range: 1.3–250 months). The 5-years-overall survival and SS rates were 66.4% and 78.1% respectively. In multivariate analysis, tumor size (≥40 mm) [RR=2.1], node involvement (RR=2.4), and poor response (<75%) to first course irradiation [RR=1.9], local relapse (RR=4.5) and distant metastases were factors of poor prognosis for SS. Five-years-LRC were 71.5% (88% for stage I, 69% for stage II, 77%, for stage IIIA and 60% for stage IIIB). Prognosis factors of LCR were tumor size (RR=2.5), response to first course of irradiation (RR=2.9). SC was 71% at 5 years. Prognosis factors of SC were tumor size (RR=1.9) and response to first course of irradiation (RR=2.4). Conclusion: The results of this series are similar to those of the literature. As well as initial tumor extension, response to first course of irradiation was found as prognostic factor on LCR, SS, SC. Our results are similar to other series and brachytherapy seems not to be deleterious. Its impact to local control remains to be evaluated. [Copyright &y& Elsevier]

Abstract: Since 2007, the Centre Alexis-Vautrin Cancer Institute in Nancy began its safety and quality assurance management policy in the department of radiation oncology. This development induced a collaborative workflow between the quality unit and the department of radiation oncology, with a definition of the responsibilities. The quality unit provides its methodology for the quality assurance, the professionals of the radiation oncology department their expertise. In parallel, a quality referee was nominated in the radiation oncology department to implement the projects for improvement, linked with the quality assurance unit, and under the control of the radiation oncology department staff. [Copyright &y& Elsevier]