Characteristics and outcome of BRCA mutated epithelial ovarian cancer patients in Italy: A retrospective multicenter study (MITO 21).

Objective: Around 15% of epithelial ovarian cancer (EOC) patients (pts) harbor a germline BRCA1 or 2 mutation, showing different features than BRCA wild-type pts. The clinical and pathological features of an Italian BRCA mutated EOC cohort were described.

Methods: We retrospectively analyzed clinical, pathological and mutational data from a cohort of Italian BRCA mutated EOC pts. treated in 15 MITO centers between 1995 and 2017.

Results: Three-hundred thirty-one pts. were recorded. Two-hundred forty (72%) and 91 (27.5%) pts. harbored a BRCA1 and BRCA2 mutation, respectively. Median age at diagnosis was 52 years. The most frequent diagnosis was a high grade serous FIGO III or IV EOC and platinum doublet in first-line was administered to almost all pts. Fifty-three % of them had no residual disease (R = 0) at surgery. Median progression-free-survival (mPFS) after first-line chemotherapy was 29 months. Expected percentage of pts. alive at 5 years was 72.5% (CI 60.2-80.8%) and R = 0 predicted a significantly longer overall survival (OS). Sixty-six pts. (19,9%) had both an EOC and a breast cancer (BC) diagnosis. The first diagnosis was BC in 81,8% of cases with a mean interval between the two diagnoses (IBTDs) of 132.4 months. Mutational data show that the founder mutation c.5266dupC in BRCA1 was the most frequently recorded.

Conclusions: This is the largest Italian BRCA mutEOC cohort. The only predictor of longer OS was R = 0. EOC pts. that developed subsequently a BC are long-term survivors.