Added value of family history in counseling about risk of BRCA1/2 mutation in early-onset epithelial ovarian cancer.

Epithelial ovarian cancer in women 40 years or younger is rare; diagnosis at this age justifies referral for genetic testing. We evaluated clinical data, family history, and risk of identifying BRCA1/2 mutations in women with early-onset epithelial ovarian cancer.,Women 40 years or younger with epithelial ovarian cancer tested for BRCA1/2 mutation at our department of human genetics between 1996 and 2012 were included. The rate of BRCA1/2 mutation was obtained; carriers were compared to noncarriers regarding clinical data.,Ten (19%) of 52 women had a BRCA1/2 mutation. This mutation was detected in 67% of women with and in 9% of the women without first-degree relatives with breast and/or ovarian cancer (P < 0.001; Fisher exact test). The median age at diagnosis was lower in the noncarriers compared to the carriers (30 vs 38 years; P = 0.014). Among the BRCA1/2 mutation carriers, 60% had serous tumors, 80% had moderately to poorly differentiated tumors, and 70% had International Federation of Gynecology and Obstetrics stage III/IV compared to 55%, 43%, and 45%, respectively, in the noncarriers.,The risk of finding a BRCA1/2 mutation in women 40 years or younger is comparable to women of all ages with epithelial ovarian cancer. Prior probability of finding a BRCA1/2 mutation in these young women is largely determined by their family history, which can help caregivers in informing ahead of genetic counseling and testing.