Germline mutations in the BRCA1 and BRCA2 genes confer increased risks for breast cancers. However, the clinical presentation of breast cancer among women who are carriers of the BRCA1 or BRCA2 (BRCA1/2 carriers) mutations is heterogenous. We aimed to identify the effects of the reproductive histories of women with the BRCA1/2 mutations on the clinical presentation of breast cancer.
We retrospectively analyzed clinical data on women with proven BRCA1 and BRCA2 mutations who were recruited to the Korean Hereditary Breast Cancer study, from 2007 to 2014.
Among the 736 women who were BRCA1/2 mutation carriers, a total of 483 women had breast cancers. Breast cancer diagnosis occurred at significantly younger ages in women who experienced menarche at 14 years of age, compared to those who experienced menarche at >14 years of age. Additionally, the number of full-term pregnancies was significantly associated with the age of diagnosis, especially in women with the BRCA2 mutation.