ESTRO 2020 Abstract Book

S200 ESTRO 2020

10 Azienda Ospedaliera della Provincia di Lecco, Radiotherapy, Lecco, Italy ; 11 Princess Margaret Cancer Centre, Radiation Oncology, Toronto, Canada ; 12 Centre Hospitalier Régional Universitaire de Besançon, Radiotherapy, Besançon, France ; 13 University of Manchester, Institute of Cancer Sciences, Manchester, United Kingdom ; 14 University Medical Center Groningen, Gynaecologic Oncology, Groningen, The Netherlands ; 15 MAASTRO, Radiation Oncology, Maastricht, The Netherlands ; 16 Auckland City Hospital, Radiation Oncology, Auckland, New Zealand ; 17 University Medical Center Utrecht, Radiation Oncology, Utrecht, The Netherlands ; 18 Comprehensive Cancer Center Netherlands, Central Data Management and Trial Coordination, Leiden, The Netherlands ; 19 Leiden University Medical Center, Pathology, Leiden, The Netherlands ; 20 Leiden University Medical Center, Medical Statistics, Leiden, The Netherlands Purpose or Objective The survival results of the PORTEC-3 trial showed a significant improvement in both overall and failure-free survival with chemoradiotherapy versus radiotherapy alone. The present analysis was performed to establish long-term adverse events and health related quality of life (HRQOL). Material and Methods The PORTEC-3 trial is an international randomized phase 3 trial. Women with high-risk endometrial cancer (stage I grade 3 with deep myometrial invasion or lymph-vascular space invasion; stage II/III endometrioid cancer; or stage I-III serous or clear cell cancer) were randomly assigned to receive pelvic radiotherapy alone (RT) or chemoradiotherapy (CTRT, concurrent 2 cycles of cisplatin followed by 4 cycles of carboplatin/paclitaxel). Adverse events (AE) were graded using CTCAE v3.0. HRQOL was measured using the EORTC QLQ-C30 and CX24 and OV28 symptom scales at baseline, after radiotherapy, and at 6, 12, 18, 24, 36 and 60 months. Symptoms rated as “quite a bit” or “very much” were considered as severe. Toxicity and HRQOL were analyzed according to treatment received. HRQOL scores were compared to an age- matched European norm-population. Clinical trial information: NCT00411138. Results Between 2006 and 2013, 660 women were randomized, of whom 579 (88%) responded for HRQOL assessment at baseline, 355 at 3 years and 237 at 5 years. Median follow up was 74.6 months. At 5 years, AE grade ≥2 were scored for 80 (39%) patients who had received CTRT vs 50 (26%) who had received RT (p=0.007). Grade 3 AE did not differ significantly between the two groups (8% vs 5%, p=0.24) at 5 years and only one grade 4 AE was reported (ileus/obstruction after CTRT). Sensory neuropathy AE persisted at long-term after CTRT in 7% (vs 0% after RT, p<0.001 at 3 and 5 years). At 3 and 5 years, more women who had CTRT reported severe tingling or numbness at HRQOL (27% vs 8%, p<0.001 at 3 years; 24% vs 9%, p=0.002 at 5 years). At 3 years, more women reported severe weakness of arms/legs (21% vs 5%, p<0.001) and lower physical (79.4 vs 86.6, p<0.001, Fig 1) and role functioning (78.3 vs 88.0, p<0.001) scores. Additionally, a trend towards more reported severe muscle or joint pain was seen (28% vs 16%, p=0.037). At 5 years, no significant differences in these HRQOL symptoms or functioning scales were seen, with scores within range of the norm population scores; however, trends towards a lower global health/QOL score (74.4 vs 79.3, p=0.045), a higher fatigue

score (24.1 vs 18.7, p=0.036) and more severe hearing problems (12% vs 4%, p=0.044) were observed after CTRT.

Conclusion Chemoradiotherapy causes significantly higher rates of grade >2 AE, worse physical functioning and higher symptom scores as compared with RT, but with clear recovery within 2 years and stable scores from then onwards. The most important long-term AE and QOL impairment after CTRT was sensory neuropathy. These long-term data are essential for patient information and shared decision-making regarding adjuvant chemotherapy for high-risk endometrial cancer. OC-0370 Surveillance or metastasis-directed Therapy for OligoMetastatic Prostate cancer (STOMP) P. Ost 1 , D. Reynders 2 , K. Decaestecker 3 , V. Fonteyne 4 , N. Lumen 3 , A. De Bruycker 4 , B. Lambert 5 , L. Delrue 6 , R. Bultijnck 4 , E. Goetghebeur 2 , G. Villeirs 6 , K. De Man 7 , F. Ameye 8 , I. Billiet 9 , S. Joniau 10 , F. Vanhaverbeke 11 1 University Hospital Ghent, Radiotherapy, Gent, Belgium ; 2 Ghent University, Department of Applied Mathematics- Computer Science and Statistics, Gent, Belgium ; 3 Ghent University Hospital, Urology, Gent, Belgium ; 4 Ghent University Hospital, Radiotherapy, Gent, Belgium ; 5 AZ Maria-Middelares, Department of Nuclear Medicine, Gent, Belgium ; 6 Ghent University Hospital, Department of Radiology, Gent, Belgium ; 7 Ghent University Hospital, Department of Nuclear Medicine, Gent, Belgium ; 8 AZ Maria-Middelares Ghent, Urology, Gent, Belgium ; 9 AZ Groeninge Kortrijk, Urology, Gent, Belgium ; 10 Catholic University Leuven, Urology, Gent, Belgium ; 11 AZ Nikolaas, Urology, Gent, Belgium Purpose or Objective Multiple randomized phase II trials suggest that metastasis-directed therapy (MDT) for oligometastatic prostate cancer (PCa) improves progression-free survival, but the majority of trials lack longer follow-up. We present the updated 5-year results from the STOMP-trial. Material and Methods In this multicentre, randomised, phase II study, asymptomatic PCa patients were eligible in case of a biochemical recurrence following primary PCa treatment with curative intent and presenting with up to 3