ESTRO 2020 Abstract Book

S604 ESTRO 2020

PO-1147 Salvage radiotherapy for recurrent endometrial cancer: predictors of outcome. H. Almasri 1 , R. Cooper 1 , F. Slevin 1 , K. Cardale 1 1 Leeds teaching hospitals NHS trust, Radiation Oncology, Leeds, United Kingdom Purpose or Objective To evaluate the outcomes of patients treated with salvage radiotherapy for vaginal recurrence of endometrial cancer and analyse potential prognostic predictors. Material and Methods Medical records of 28 patients treated with salvage radiotherapy for biopsy-proven recurrent vaginal disease between 2012 and 2016 were retrospectively reviewed. All were initially treated with surgery without adjuvant pelvic radiotherapy. Patients’ age, initial stage, grade, histology, size of recurrent disease, whether or not it invaded adjacent organs and pelvic lymph node status were recorded as well as radiotherapy techniques and cumulative doses. Overall survival (OS), disease-free survival (DFS), and local control (LC) were estimated using Kaplan-Meier method and compared using Log-rank test. Results Median follow-up time was 31 months (range,3-123). Median age at recurrence was 68 years (range,57-80). Median time from surgery to recurrence was 15 months (range,2-84). Initial FIGO (2009) stage was IA in 13/28 (46%), IB in 11/28 (39%), and II in 4/28 (14%). The histology was endometrioid in 21/28 (75%) and non-endometrioid in 7/28 (25%). 12/28 (43%) had FIGO grade 3. Invasion of bowel, bladder or ureter was present in 5/28 (18%). Salvage radiotherapy was HDR brachytherapy in 5/28 (18%), combined external beam and HDR brachytherapy 8/28 (29%), and external beam radiotherapy alone in 15/28 (53%). 10/15 (67%) patients treated with external beam radiotherapy alone received 45 Gy (1.8Gy/fraction) followed by a sequential boost (dose:9-18 Gy), while 5/15 (30%) received a single phase of 50 Gy (2.5 Gy/fraction). Median time to disease progression after salvage radiotherapy was 11 months (range,3-32). Local control rate at 3 years was 63.3%. 3-year and 5-year OS were 66.9% and 51.1%, respectively. Patients with non-endometrioid histology had significantly inferior OS compared to endometrioid histology (3-year OS 42.9% vs 75.2%, log-rank p=0.009). Invasion of adjacent structures was associated with poorer OS (3-year OS= 20% vs 77%, log-rank p=0.005). A trend for improved OS was observed for tumours ≤1.5cm (log-rank p=0.057) and with the use of brachytherapy (log- rank p=0.2). Median DFS was 16 months. 3-year and 5-year DFS were both 24%. Distant metastasis was the first site of disease progression in 10/17 (58.8%) patients who progressed. Significantly lower DFS was observed with invasion of adjacent structures (median DFS, 24 vs 6 months, log-rank p=0.003). Use of brachytherapy alone or after external beam yielded better DFS (median DFS, 24 vs 11 months, with vs without bracytherapy), yet this did not reach statistical significance, (log-rank p=0.06). A trend for better DFS was also observed for smaller tumour size (≤1.5cm), and EQD2 >70 Gy. Conclusion Approximately half of patients treated with salvage radiotherapy for recurrent endometrial cancer survive beyond 5 years. Disease progression usually occurs at distant sites. Poor outcome is predicted by non- endometrioid histology and advanced local disease. PO-1148 Implementation of a cervix cancer specific patient reported outcome measure in clinical practice S. Atallah 1 , L. Barbera 2 , M. Folwell 3 , D. Howell 4 , A. Liu 5 , C. Jennifer 6 1 Princess Margaret Cancer Centre- University Health Network, Department of Radiation Oncology- University of Toronto, Toronto, Canada ; 2 Cross Cancer Institute, Department of Oncology- University of Calgary, Toronto, Canada ; 3 Royal Victoria Regional Health Center,

Department of Radiation Oncology- University of Toronto, Barrie, Canada ; 4 Princess Margaret Cancer Centre- University Health Network, Department of Psychosocial Oncology- University of Toronto, Toronto, Canada ; 5 Princess Margaret Cancer Centre- University Health Network, Department of Biostatistics- University of Toronto, Toronto, Canada ; 6 Princess Margaret Cancer Centre, Radiation Oncology, Toronto, Canada Purpose or Objective To evaluate implementation of a cervix cancer specific patient-reported outcome measure, the European Organization for Research and Treatment of Cancer Quality of Life Cervical Cancer module (EORTC QLQ-CX24), into gynecologic oncology clinics. Material and Methods This was a prospective, multi-institutional, cross-sectional study involving cervix cancer patients previously treated with curative intent radiotherapy who were attending routine follow-up appointments. Between January 2017 and August 2018, eligible patients were approached to complete the EORTC QLQ-CX24 prior to their clinical encounter and then review it with their oncologist. Patient and oncologist experience was evaluated using Feedback Questionnaires following the encounter. Descriptive statistics were used to summarize the results of the EORTC QLQ-CX24 and Feedback Questionnaires. Open-ended questions within the Feedback Questionnaires were analyzed to identify themes. Results Eighty-four patients consented to participate in the study. Of these, 80 (95.2%) completed the EORTC QLQ-CX24 and 76 (90.4%) completed both the EORTC QLQ-CX24 and the Feedback Questionnaires. There were high rates of completion for most items within the EORTC QQL-CX24 (93-98%), except for items pertaining to vaginal symptoms and sexual health (34-35%). All eligible oncologists participated (n=9). Overall, patients and oncologists positively endorsed use of the questionnaire during clinical encounters. The majority of patients (80%) and oncologists (89%) reported use of the questionnaire improved communication, including discussion of sensitive topics. Interestingly, only a minority of patients and oncologists stated a perceived preference for electronic completion (18% and 44%, respectively) Conclusion Implementation of the EORTC QLQ-CX24 in gynecologic oncology clinics was feasible and acceptable according to patients and oncologists. PO-1149 Long-term results of high-precision salvage radiation therapy after radical prostatectomy P. Bulychkin 1 , S. Tkachev 1 , V. Matveev 2 1 N. N. Blokhin Cancer Research Center- Russian Academy of Medical Sciences, radiation oncology, Moscow, Russian Federation ; 2 N. N. Blokhin Cancer Research Center- Russian Academy of Medical Sciences, oncourology, Moscow, Russian Federation Purpose or Objective The aim of our study is to analyze the long-term results of salvage radiation therapy (SRT) for patients with recurrence of prostate cancer (PCa) after radical prostatectomy (RP). Material and Methods Biochemical recurrence after radical prostatectomy – subsequent detectable PSA level after radical prostatectomy that increases on 2 or more subsequent laboratory determination. Clinical recurrence – is a type of biochemical recurrence in which a substrate of a locoregiolal recurrence tumor is detected by modern Poster: Clinical track: Prostate