EP575\u2005Patterns of relapse in endometrial cancer

Abstract

Introduction/Background The treatment of patients with high risk endometrial cancer remains controversial, with PORTEC 3 reporting no significant overall survival benefit in patients receiving chemoradiotherapy compared with radiotherapy alone. In this study we reviewed the outcomes of patients who received adjuvant radiotherapy (± chemotherapy) to review patterns of relapse. Methodology This retrospective study reviewed the clinical notes of 163 patients who were referred for adjuvant radiotherapy in Kent Oncology Centre, England between January 2012 - December 2016. Follow-up clinic appointments and scans were reviewed. Results 163 patients received conformal adjuvant pelvic radiotherapy to a dose of 45Gy in 25 fractions. During the follow-up period 31 patients relapsed. The mean time to relapse was 14.7 months (range 1.3–37.6 months). Table 1 illustrates the staging, histology and treatments received by the patients who relapsed. 28 of the 31 patients with recurrent disease had widespread metastatic disease when diagnosed with recurrent disease, and 3 patients had local recurrence only. The sites of local recurrence, details of the histology and treatment received and site of recurrence in relation to the PTV and isodose level are illustrated in table 2. Conclusion The majority of patients with recurrent endometrial cancer relapsed with systemic disease. No patients with local recurrence only, relapsed within the radiotherapy CTV and all three patients with local relapse had endometriod histology. Although no overall survival benefit with systemic treatment was reported in Portec 3, our results are consistent with the Portec 3 findings that endometrial disease recurrence is usually a systemic event and local recurrence is rare. Our focus for improving outcomes from endometrial cancer should be on systemic therapies. Disclosure Nothing to disclose. Abstract EP575 Table 1 FIGO Stage Number of Patients Histology % received adjuvant brachytherapy % received adjuvant chemotherapy 1a 2 100% Carcinosarcoma 0% 100% 1b 5 20% Carcinosarcoma 40% Endometriod 20% Mixed 20% Serous 20% 20% 2 7 86% Endometriod 14% Mixed 72% 14% 3a 2 50% Endometriod 50% Serous 0% 0% 3b 3 33% Carcinosarcoma 67% Serous 67% 67% 3c1 5 20% Carcinosarcoma 20% Clear cell 60% Endometriod 80% 20% 3c2 4 25% Carcinosarcoma 25% Endometriod 25% Missing record 25% Serous 25% 100% 4 (unspecified) and 4a 2 50% Carcinosarcoma 50%Serous 0% 100% (both 4 cycles pre-op; 2 cycles post-op) 4b 1 100% Carcinosarcoma 0% 100% Abstract EP575 Table 2 Patient Histology Stage and grade at diagnosis Site of recurrence Did patient have brachytherapy? Did patient receive adjuvant chemotherapy? Relation to CTV and isodose A Endometriod 2 (Grade 2) Left common iliac, external iliac and pre-sacral nodes Yes No Within CTV; covered by 95% B Endometriod 2 (Grade 2) Vagina Yes No Inferior to CTV C Endometriod 3c1 (Grade 1) Vaginal vault Yes Yes Within CTV; covered by 95%