Abstract B21: BRCA mutation status is not associated with better long-term survival from epithelial ovarian cancer.
Authors: Kotsopoulos Joanne , Fan Isabel , McLaughlin John , Rosen Barry , May Taymaa , Risch Harvey , Sun Ping , Narod Steven 
Published: May 2016

Background: Previous studies have described better survival for women with epithelial ovarian cancer and an inherited BRCA1 or BRCA2 mutation compared to those without a mutation. Most of these studies had short follow-up periods. It is of importance to clarify the disease-specific mortality outcomes of BRCA mutation carriers using data from an unselected population with long follow-up. The overall goal of the current study was to evaluate the long-term mortality outcomes based on BRCA mutation status among women diagnosed with epithelial ovarian cancer.

Methods: Women with unselected epithelial ovarian cancer diagnosed in Ontario, Canada from 1995-1999 and 2002-2004 included in the current study. Tumor histology was based on review of pathology records while clinical and treatment information was obtained from individual medical records. Survival status was determined by linkage to the Ontario Cancer Registry which provides information on date and cause of death. We also estimated the annual mortality for members of the cohort based on a life-table approach for each one-year period after the date of diagnosis until 12 years after diagnosis.

Results: Of the 1,421 women with a diagnosis of invasive epithelial ovarian cancer, 109 (7.7%) had a BRCA1 mutation and 68 (4.8%) had a BRCA2 mutation while 1,244 (87.5%) were non-carriers. The mean age at diagnosis (in years) was 57.7 for non-carriers, 50.9 for BRCA1 mutation carriers and 57.4 for BRCA2 mutation carriers. Seventy-three percent of BRCA1 mutation carriers, 78% of BRCA2 mutation carriers and 52% of non-carriers were diagnosed with a serous tumor. The two-year survival rates were 78% for non-carriers, 85% for BRCA1 mutation carriers and 100% for BRCA2 mutation carriers. The five-year survival rates were 56% for non-carriers, 52% for BRCA1 mutation carriers and 61% for BRCA2 mutation carriers. The 12-year survival rates were 44% for non-carriers, 32% for BRCA1 mutation carriers and 28% for BRCA2 mutation carriers. At 12-years, the survival experience of BRCA mutation carriers was significantly worse than non-carriers (OR = 1.81; P &lt; 0.0001). Among the women who died, the mean duration from diagnosis to death was 4.47 years for non-carriers, 4.78 years for BRCA1 mutation carriers and 5.13 years for BRCA2 mutation carriers.

Conclusion: Findings from this study suggest a short-term survival advantage among women with a BRCA mutation but no impact on overall, long-term survival. This observation may reflect a better acute response of BRCA carriers to chemotherapy that is eventually diminished over time.

Citation Format: Joanne Kotsopoulos, Isabel Fan, John McLaughlin, Barry Rosen, Taymaa May, Harvey Risch, Ping Sun, Steven Narod. BRCA mutation status is not associated with better long-term survival from epithelial ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: Exploiting Vulnerabilities; Oct 17-20, 2015; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(2 Suppl):Abstract nr B21.