ESTRO 2020 Abstract book

S36 ESTRO 2020

fraction(fx), total number of fx), and perceived barriers and facilitators. Results There were 1,259 European respondents (57%) from 46 countries, the majority practicing in the European Union- 28 (86%). Highest response rates came from Italy (12%), the United Kingdom (11%), Spain (10%), Germany (8%) and Denmark (5%). In breast cancer, post-lumpectomy, hypofractionation uptake was 89% in node negative and 48% in node positive disease; post-mastectomy, rates were 50% and 35% respectively (p<0.0001). In prostate cancer, uptake was in 67% in low risk, 63% intermediate, 49% high-risk and 28% of cases requiring pelvic irradiation (p<0.00001). For palliation of bone metastases, 96% favored hypofractionation. In case of hypofractionation for breast cancer, 64% prescribed 2.5-3Gy in 15-16 fx irrespective of indication. Higher fraction numbers were noted in prostate varying by indication (22% 3-3.5Gy/20 fx in low-intermediate risk & 18% 2.5-3Gy/28 fx in high-risk or pelvic irradiation disease). Single fraction (8-9Gy) was favored in uncomplicated bone metastasis (38%) whereas 5 fx of 4- 5Gy was favored in cases complicated by fracture (21%), cord compression (21%) or soft tissue component (25%). Evidence (95%), equivalent local control (93%) and equivalent toxicity (79%) were consistently the main facilitators in curative setting. Higher barriers to hypofractionation were observed in prostate compared to breast cancer, chiefly late toxicity (54% vs. 38%, p<0.0001), lack of long-term data (39% vs. 33%, p<0.058) and acute toxicity (37% vs. 21%, p<0.00001).

Results Response rate was 79% representing 37 of 47 centres for analysis. In 2018, there were 411 ROs in practice compared with 379 ROs in 2016 from the 2017 survey for these same 37 centres, demonstrating an 8.4% increase in staffing. Approximately half (211 ROs) were ≥ 46 years old. The RO full-time equivalent (FTE) to RO ratio was 0.92 with 77 ROs (18.7%) having less than 1.0 FTE clinical activities due to administration, research, or part-time employment. National male-to-female ratio was 1.5:1 and was age- dependent. Regional male-to-female ratios varied widely with the highest ratio in Ontario (3.4:1) and lowest in Quebec (0.8:1). Average annual consultations per FTE-RO in 2018 was 261/year compared to 262/year in 2016 for these 37 centres. The majority of ROs were employed as contractors (53.0%) and remunerated with a hybrid fixed and performance-based compensation model (55.7%). Most centres (40.5%) reported an increase in compensation from 2016 to 2018, whereas 37.8% conveyed no change and 21.6% experienced lower compensation. Approximately one-quarter (24.7%) of the 190 reported linear accelerators in operation were older than 10 years and operating beyond the equipment’s recommended lifespan compared to 22.5% (42/187) in 2016 (P = 0.12). Lung SBRT utilization among Canadian centres was 91.9% (34 of 37 centres), while intracranial SRS and non-lung SBRT utilization rates were 51.4% (19/37 centres) and 59.5% (22/37 centres), respectively. Only 7 of 17 centres (41.2%) located in regions with ≤ 150,000 persons had SRS or non- lung SBRT practice compared to 16 of 20 centres (80.0%) in regions with > 150,000 persons (P = 0.02). Conclusion The Canadian RO workforce continues to demonstrate incremental growth in staffing with stable annual caseload in the short-term compared to the 2016 data. Government funding is required to replace aging equipment in Canada. Lower intracranial SRS and non-lung SBRT utilization in smaller community settings suggest geographic disparity of advanced technologies that may limit cancer care accessibility of modern practice techniques for Canadian cancer patients. OC-0076 Insights into the evidence-based practice of hypofractionated radiotherapy in Europe B. Tawk 1,4 , D. Rodin 2 , G. Axelsson 3 , Y. Lievens 4 1 Universitätsklinikum Heidelberg, Radiation oncology, Heidelberg, Germany ; 2 Radiation Medicine Program- Princess Margaret Cancer Centre, University of Toronto- Radiation Oncology, Toronto, Canada ; 3 European Society for Radiotherapy and Oncology, Public Affairs, Brussels, Belgium ; 4 Ghent University Hospital and Ghent University, Radiation Oncology, Brussels, Belgium ; 4 Bouchra Tawk, German Cancer Consortium (DKTK) core site Heidelberg, Germany Purpose or Objective Effıcacy of hypofractionationed radiotherapy has been demonstrated in clinical trials. We previously reported on global practice patterns of hypofractionation in a worldwide survey distributed through the ESTRO Global Impact of Radiotherapy in Oncology (GIRO) initiative. This subgroup analysis aims to evaluate practice background of radiotherapists, uptake of hypofractionation, its facilitators and barriers in curative breast and prostate cancer, and for bone metastases across Europe. Material and Methods Between January and December 2018, 2,259 radiation oncologists responded to an international anonymous electronic survey distributed in English, Spanish, Japanese and Mandarin. Demographic and professional characteristics were collected. Preference for hypofractionation was evaluated across breast, prostate, cervix and bone metastases in curative and palliative clinical scenarios. Respondents reported preferred fractionation regimens for each scenario (dose per