The influence of carrying BRCA pathogenic mutations in ovarian cancer and its platinum-sensitivity: 5-year experience of a tertiary center.

Abstract

e17572 Background: Platinum-based chemotherapy still remains as the backbone treatment in ovarian cancer (OC) and its homologous tumors (primary peritoneal PP and fallopian tube FT cancer). BRCA mutational status is a sensitivity predictor to platinum chemotherapy. The aim of this study is to quantify the benefit of carrying a BRCA mutation along the subsequent platinum treatments and beyond. Methods: A descriptive, retrospective, single center study was developed in a tertiary hospital. OC, PP and FT neoplasms in stage III/IV, treated between 01/2015 and 12/2020 were included. Demographic characteristics, BRCA and HRD pathogenic mutational status, platinum-sensitive survival (PSS), platinum-resistant survival (PRS) and overall survival were analyzed. A p-value of < 0.05 was considered statistically significant. Results: 116 patients were recruited (96 OC, 9 PP, 7 FT). 100 were non-BRCA mutated (including 2 germline BRIP, 1 RAD51C), 16 were BRCA-mutated (8 germline BRCA1, 7 germline BRCA2, 1 somatic BRCA2). 83 (71.6%) were stage III at diagnosis and 33 (28.4%) stage IV. Histologically, 90 cases were serous subtype (77.6%), 40.5% were grade 3. Mean age was 62.1 years. 90 (77.6%) received oncological surgery (debulking or interval procedure). A table is annexed with demographic characteristics without unbalanced distribution.Between BRCA-mutated group and non-mutated, the mean of platinum-based treatments was 2.63 (range 1-7) vs 2.49 (1-8), median PSS 42,8 months (9.7-80.1) vs 24.5 (2-78.9) HR 0.27 (95% IC 0.07-0.88. Log rank p-value 0.019), median PRS 20.3 (16-24.9) vs 9 (1.3-67.4) HR 1.1 p-value 0.715, and overall survival of 43.4 (11.3-81.4) vs 29 (0.7-78.9) HR 0.8 p-value 0.083. In contrast, histology factors, tumor markers, type of performed surgery, maintenance treatments and nonplatinum treatments didn’t result in a significant benefit as being carrier of BRCA mutation showed. Conclusions: Our analysis confirms that the platinum sensitive survival is deeply depend on the BRCA mutational status, remaining the most beneficial prognostic and predictive factor in the operated III/IV stages.[Table: see text]