Family History of Breast and Ovarian Cancers and BRCA1 and BRCA2 Mutations in a Population-Based Series of Early-Onset Breast Cancer

Abstract

Almost half (48%) of women in southern Sweden with early-onset breast cancer have some family history of breast or ovarian cancer, and 9.0% of early-onset breast cancer cases are associated with a germline mutation in BRCA1 or BRCA2. Mutation carriers were more prevalent among young women, women with at least one first- or second-degree relative with breast or ovarian cancer, and women with bilateral breast cancer.