Second primary breast cancer in BRCA1 and BRCA2 mutation carriers: 10-year cumulative incidence in the Breast Cancer Family Registry

Abstract

BReast CAncer genes 1 and 2 (BRCA1 and BRCA2) mutation carriers diagnosed with breast cancer are at increased risk of developing a second primary breast cancer. Data from high-risk clinics may be subject to different biases which can cause both over and underestimation of this risk. Using data from a large multi-institutional family registry we estimated the 10-year cumulative risk of second primary breast cancer including more complete testing information on family members. We prospectively followed 800 women diagnosed with breast cancer from the Breast Cancer Family Registry (BCFR) who were carriers of a BRCA1 or BRCA2 pathogenic mutation or a variant of unknown clinical significance. In o..