LAUSR

PURPOSE Stereotactic body radiotherapy to vertebral column remains uncommon practice and only relevant in selected group of patients. The main objective of the study was to describe the current state of medical practices of stereotactic body radiotherapy to vertebral column in France in 2016 and to assess the diversity of practices to identify areas for improvement and establish a common database set for this technique. MATERIALS AND METHODS A questionnaire was written with contribution of a medical physicist, a radiation oncologist, an information technologist and a radiotherapy resident. The questionnaire was distributed online to a radiation oncologists and a medical physicists partner of selected French radiotherapy specialized centres that provide stereotactic body radiotherapy to vertebral metastasis from April to June 2016. The questionnaire surveyed the following topics: patients' selection, simulation, targeted volume and organs at risk delineation, prescription, dosimetric implementation and image guidance. RESULTS A total of 31 centres were surveyed. Seventy eight per cent of centres (n=21) completed the questionnaire. The "ideal" patient for spine stereotactic radiotherapy according to these institutions has a good performance status, a long life expectancy, controlled primary tumour with oligometastatic spread. The most prescribed protocol was 30Gy in three fractions. For clinical target volume delineation, about two thirds of centres used the International Spine Radiosurgery Consortium (ISRC) recommendations (Noël G et al.,2006). CONCLUSION This study identified some consistency of practices in some aspects despite the lack of consensus guidelines. Nevertheless, further studies are needed to establish consensus of planning and treatment.