ESTRO 2020 Abstract book

S344 ESTRO 2020

OC-0569 Incidence of severe gastrointestinal and urinary fistulas, bleeding and strictures: EMBRACE results A.S. Vittrup 1 , K. Kirchheiner 2 , K. Tanderup 1 , N.B.K. Jensen 1 , S. Spampinato 1 , L.U. Fokdal 1 , C. Kirisits 2 , C. Haie-Meder 3 , J.C. Lindegaard 1 , M. Schmid 2 , A. Sturdza 2 , U. Mahantshetty 4 , I.M. Jürgenliemk-Schulz 5 , P. Hoskin 6 , B. Segedin 7 , K. Bruheim 8 , B. Rai 9 , E. Wiebe 10 , E. Van der Steen-Banasik 11 , R. Cooper 12 , E. Van Limbergen 13 , M. Sundset 14 , B.R. Pieters 15 , R. Nout 16 , R. Pötter 2 1 Aarhus University Hospital, Department of Oncology, Aarhus, Denmark ; 2 Medical University of Vienna/General Hospital of Vienna, Department of Radiation Oncology- Comprehensive Cancer Center, Vienna, Austria ; 3 Gustave-Roussy, Department of Radiotherapy, Villejuif, France ; 4 Tata Memorial Hospital, Department of Radiation Oncology, Mumbai, India ; 5 University Medical Centre Utrecht, Department of Radiation Oncology, Utrecht, The Netherlands ; 6 Mount Vernon Hospital, Cancer Centre, Northwood, United Kingdom ; 7 Institute of Oncology Ljubljana, Department of Radiotherapy, Ljubljana, Slovenia ; 8 The Radium Hospital- Oslo University Hospital, Department of Oncology, Oslo, Norway ; 9 Postgraduate Institute of Medical Education and Research, Department of Radiotherapy and Oncology, Chandigarh, India ; 10 Cross Cancer Institute and University of Alberta, Department of Oncology, Edmonton, Canada ; 11 Radiotherapiegroep Arnhem, Department of Radiotherapy, Arnhem, The Netherlands ; 12 St James's University Hospital, Leeds Cancer Centre, Leeds, United Kingdom ; 13 UZ Leuven, Department of Radiation Oncology, Leuven, Belgium ; 14 St. Olavs Hospital, Clinic of Oncology and Women's Clinic, Trondheim, Norway ; 15 Amsterdam University Medical Centers- University of Amsterdam, Department of Radiation Oncology, Amsterdam, The Netherlands ; 16 Leiden University Medical Center, Department of Radiation Oncology, Leiden, The Netherlands Purpose or Objective The development of image-guided adaptive brachytherapy (IGABT) based on MRI has improved local control and survival in locally advanced cervical cancer (LACC). The aim of this report was to describe severe gastrointestinal and urinary fistula, bleeding and stricture events in the intErnational study on MRI-guided BRAchytherapy in locally Advanced CErvical cancer (EMBRACE), and relate them to FIGO stage and high-risk clinical target volume (CTV HR ). Material and Methods The EMBRACE study enrolled 1416 patients with LACC from 2008 to 2015. Treatment included radio(chemo)therapy and MR IGABT. Morbidity was prospectively assessed according to CTCAE v.3.0 every 3 months (1 st year), every 6 months (2 nd and 3 rd year) and yearly thereafter. Gastrointestinal and urinary fistulas, bleeding, and strictures grade 3-5 (severe events) were summarised as maximum grade per patient during follow-up (crude incidences). In addition, severe events were reported according to: 1) FIGO stage (I-II, III, IVA, IVB) and tested for differences with chi-square test or Fischer’s exact test, and 2) CTV HR volume at first brachytherapy fraction (divided into 3 groups by the 33.3 and 66.6 percentiles) and tested for differences with Spearman´s rank-order correlation. Results Overall, 1246 patients treated according to protocol and with available follow-up on late morbidity from 3 months onwards were included in the analysis. Median follow-up was 48 months (IQR 20-61). Table 1 shows crude incidences

Conclusion To our knowledge, this is the first time that visualization and quantification of bowel motility by a non-invasive 3D cine-MRI was shown feasible at time of radiotherapy. The variability of the bowel motion was high within and between patients. Additionally, the median bowel motility was significantly decreased after EBRT in almost all patients. This new tool can be used for future studies evaluating the clinical relevance of bowel motion during radiotherapy.