Table 2.

Human cancers arising in BRCA1 or BRCA2 mutation carriers

Cancer type	BRCA1 mutations	BRCA2 mutations	Notes
Breast	70–80% lifetime risk	50–60% lifetime risk	Breast and ovarian cancer is the dominant cancer predisposition in BRCA1 and BRCA2 mutation carriers. BRCA1 mutation carriers develop breast and ovarian cancer at a younger age than BRCA2 mutation carriers113
Ovarian	50% lifetime risk	30% lifetime risk	Breast and ovarian cancer is the dominant cancer predisposition in BRCA1 and BRCA2 mutation carriers. LOH of the wild-type BRCA allele is always found
Prostate	Ashkenazi Jewish founder mutations are associated with increased risk	20-fold increased risk	<1% of BRCA2 mutation carriers have prostate cancer. Prostate cancer is even rarer in BRCA1 mutation carriers, except in members of the Ashkenazi Jewish population with BRCA1 mutations
Pancreatic	Anecdotal evidence and case reports only	Tenfold increased risk	<1% of BRCA2 mutation carriers have pancreatic cancer. No incidence has been clearly documented in BRCA1 mutation carriers
Gastric	None reported	Limited reports	It is unclear whether stomach cancer is associated with BRCA2 mutations
Others	None reported	Brain, medulloblastoma, pharyngeal, CLL and AML	Fanconi anaemia subtype D1 (caused by BRCA2 mutations) is associated with cancer of the central nervous system
Fallopian tube	Observed, but rare	Rare	This cancer type is like ovarian cancer, but it is a rare cancer overall and is still uncommon in BRCA mutation carriers

AML, acute myeloid leukaemia; CLL, chronic lymphocytic leukaemia; LOH, loss of heterozygosity.