ESTRO 2022 - Abstract Book

S748

Abstract book

ESTRO 2022

the acute morbidities will be provided at the ESTRO conference. Radiation-associated late morbidities are currently investigated as part of 10-year follow-up.

OC-0830 Systemic recurrence after primary chemoradiation in cervical cancer patients – an EMBRACE analysis

J. Knoth 1 , R. Nout 2 , U. Mahantshetty 3 , I. Jürgenliemk-Schulz 4 , C. Haie-Meder 5 , L.U. Fokdal 6 , A. Sturdza 7 , P. Hoskin 8 , B. Segedin 9 , K. Bruheim 10 , F. Huang 11 , B. Rai 12 , R. Cooper 13 , E. van der Steen-Banasik 14 , E. van Limbergen 15 , B.R. Pieters 16 , L.T. Tan 17 , S. Kannan 3 , A.A. de Leeuw 4 , N. Nesvacil 7 , K. Tanderup 6 , C. Kirisits 7 , J.C. Lindegaard 6 , R. Pötter 7 , M.P. Schmid 7 1 Medical University of Vienna/General Hospital of Vienna, Department of Radiation Oncology, Comprehensive Cancer Center, Vienna, Austria; 2 Erasmus University Rotterdam, Department of Radiation Oncology, Rotterdam, The Netherlands; 3 Tata Memorial Hospital, Department of Radiation Oncology, Mumbai, India; 4 University Medical Centre Utrecht, Department of Radiation Oncology, Utrecht, The Netherlands; 5 Gustave-Roussy, Department of Radiotherapy, Villejuif, France; 6 Aarhus University Hospital, Department of Oncology, Aarhus, Denmark; 7 Medical University/General Hospital of Vienna, Department of Radiation Oncology, Comprehensive Cancer Center, Vienna, Austria; 8 Mount Vernon Hospital, Mount Vernon Cancer Centre, Northwood, United Kingdom; 9 Institute of Oncology Ljubljana, Department of Radiotherapy, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia; 10 The Norwegian Radium Hospital, Oslo University Hospital, Department of Oncology, Oslo, Norway; 11 Cross Cancer Institute and University of Alberta, Department of Oncology, Edmonton, Canada; 12 Postgraduate Institute of Medical Education and Research, Department of Radiotherapy and Oncology, Chandigarh, India; 13 St James's University Hospital, Leeds Cancer Centre, Leeds, United Kingdom; 14 Radiotherapiegroep Arnhem, Department of Radiotherapy, Arnhem, The Netherlands; 15 UZ Leuven, Department of Radiation Oncology, Leuven, Belgium; 16 University of Amsterdam, Department of Radiation Oncology, Amsterdam University Medical Centers, Academic Medical Center, Amsterdam, The Netherlands; 17 Addenbrooke´s Hospital, Cambridge University Hospitals, Department of Oncology, Cambridge, United Kingdom Purpose or Objective To evaluate systemic recurrence within the prospective observational multi-centre IntErnational study on MRI-guided BRAchytherapy in locally advanced CErvical Cancer (EMBRACE) cohort. Materials and Methods Data from 1416 patients with locally advanced cervical cancer (LACC) treated from 2008-2015 in 24 centres were collected. Treatment consisted of pelvic +/- para-aortic external beam radiotherapy with 45-50Gy (1.8-2.0 Gy per fraction), concurrent chemotherapy (Cisplatin 40mg/m ² weekly) (RCHT) and MRI based image-guided adaptive brachytherapy (IGABT). Follow-up (FU) visits were scheduled at 3 months intervals for the first year, 6 months intervals for the second and third year and yearly intervals thereafter. In case of recurrent disease only the first site of recurrence was registered. A systemic recurrence (SR) was defined as any first recurrent disease outside the pelvis. Descriptive statistics, uni- and multivariate analyses (MVA) were performed to describe patterns of recurrence and risk factors using the following variables: age, haemoglobin and white blood cell count at diagnosis, WHO performance score, hydronephrosis, smoking status, FIGO 2009 stage, histology, maximum tumour dimension, involved lymph node regions (N0 vs pelvic vs common iliac vs para-aortic (PAN), no. of chemotherapy cycles, CTV HR volume at IGABT, D90 for CTV HR , overall treatment time. Risk factors were evaluated for the overall cohort and for initially node negative and node positive patients (NNP/NPP), separately. Results 1318 patients were eligible for analysis. FIGO 2009 stages were IB1 (8%), IB2 (9%), IIA (5%), IIB (52%), IIIA (1%), IIIB (14%), IVA (3%) and IVB (PAN only, 7%), N0 = 48%, N1 = 52%. After a median FU of 51 months, SR was reported in 243 patients (18%). Of these, 31 (13%) had a simultaneous local and 77 (32%) had a simultaneous pelvic nodal recurrence. Median time to SR was 12 months (1-97). Most common sites for SR were PAN (n=106), lungs (n=61), unknown (n=41), mediastinal lymph nodes (n=36), bones (n=23), peritoneum(n=19) and liver (n=17). Risk factors for SR in the overall cohort are summarized in table 1. Nodal status (with risk increasing the more cranial the nodal region) and histology were the strongest risk factors for SR in the overall cohort. Additional risk factors in NNP were dose to the D90 of CTV HR at IGABT and presence of tumour necrosis on MRI. Additional risk factors in NPP were CTV HR >45cm ³ at IGABT and haemoglobin level at diagnosis. FIGO 2009 stage was not significant in any analysis. 5-year systemic control based on these factors is shown in table 2.