898PPRIMARY CYTOREDUCTIVE SURGERY (PCS) VS NEOADJUVANT CHEMOTHERAPY (NACT) FOR ADVANCED OVARIAN CARCINOMA (AOC): DECISION CRITERIA AND EFFICACY OUTCOMES

Abstract Aim: PCS is the standard of care for aOC but NACT and interval debulking surgery (IDS) are acceptable treatment options for patients (pts) with stages IIIC and IV OC. Our aims are to characterize OC pts treated with PCS or NACT in our centre and to analyse decision criteria and efficacy outcomes of both strategies. Methods: All pts with ovarian tumours registered at the Southern Portuguese Cancer Registry (ROR-Sul) between 2006-2011 were reviewed for age at diagnosis, histology, FIGO stage, treatment (none, surgery and/or CT), progression free survival (PFS), overall survival (OS), criteria for NACT, number of platinum based CT cycles and residual macroscopic disease. Results: From 345 pts registered with ovarian tumours, 258 were epithelial ovarian cancers (EOC) (75%). EOC pts had a median age of 62 yrs (10-90); 64 (25%) were treated with surgery alone, 53 (21%) with NACT (stages IIIB-3, IIIC-15, IV-29) and 94 (37%) with PCS (25% stages IA-IC; 23% IIA-IIIA; 51% IIIB-IV).Other pts (17%) were not treated at our centre (only pathology review, multidisciplinary decision or death before treatment). For similar stages (IIIB-IV), median age was higher for NACT pts (64 yrs, 36-90) vs 59 yrs (33-82); median number of CT cycles was 8 (NACT) and 6 (PCS). Nine pts in the NACT group progressed and died before IDS. Complete resection of macroscopic disease was achieved in 24 (55%) of NACT pts and in 17 (36%) of PCS pts. Median OS and PFS were 29,2 and 8,1 months (NACT) and 38,1 months and 10,6 months (PCS). Bad prognosis pathology (mucinous/clear cell) was observed in 10 pts (3 NACT, 7 PCS). NACT decision was based on radiological criteria (74% of cases) such as implants >2cm outside the pelvis, lymphadenopathies above renal hilum, pre-sacred retroperitoneal disease or liver metastasis. In 14 pts (26%), comorbidities contraindicated upfront surgery. Conclusions: NACT was mostly decided for older pts with contraindications for upfront surgery and/or with radiologically determined unresectable disease. Observed OS was similar to that observed in trials with more fit pts. OS for the PDS group is in line with previous reports of single centre studies with experience in OC treatment. Disclosure: All authors have declared no conflicts of interest.