Cancer risks for male carriers of germline mutations in BRCA1 or BRCA2: a review of the literature

Abstract

Major risks conferred by BRCA1 and BRCA2 in women are for cancers of the breast, ovary, fallopian tube, and peritoneum. Male carriers of mutations in BRCA1 or BRCA2 are also susceptible to cancer; however, their risks remain poorly understood and their optimal clinical management has not yet been defined. This article reviews studies that estimate risk associated with mutations in BRCA1 or BRCA2, with a focus on the cancer sites most relevant to men. Male BRCA1 mutation carriers are at increased risk of cancers of the prostate and breast. Evidence supporting increased susceptibility to colon cancer is limited. In contrast to women, who have a greater lifetime risk of cancer with mutations of the BRCA1 gene, BRCA2 is the more important gene for men. The spectrum of cancers is wide for BRCA2 and some studies report that the overall cancer risk for male BRCA2 carriers exceeds the risk for female carriers. In particular, the relative risk to male BRCA2 mutation carriers is high before age 65 years, largely attributable to breast, prostate, and pancreatic cancers. BRCA2 mutation carriers are also at risk of stomach cancer and melanoma (of the skin and eye). Additional research into risks to male BRCA1 or BRCA2 mutation carriers is necessary, specifically to determine the magnitude of excess cancer risk among BRCA2 carriers and to increase our understanding of the basis for the observed site-specificity in cancer development.