Phenocopy breast cancer rates in Israeli BRCA1 BRCA2 mutation carrier families: is the risk increased in non-carriers?

BRCA1 and BRCA2 mutation carriers have an increased risk for developing breast (and ovarian) cancer. Non-carriers from within such families (=true negatives) are counseled that their risk for developing breast cancer is similar to that of the average-risk population. Breast cancer diagnosed in a non-carrier from a family with a known mutation is coined phenocopy.

Appendectomy and cancer risk in Jewish BRCA1 and BRCA2 mutation carriers.

Previous studies suggested that appendectomy may affect cancer risk in the general population. No data on the effect of appendectomy on cancer risk in BRCA1 and BRCA2 carriers is available. Data on appendectomy, cancer type, and age at diagnosis were collected from BRCA1 (n = 677) and BRCA2 (n = 270) female Jewish Israeli mutation carriers counseled in a single medical center.

Cancer risk in Jewish BRCA1 and BRCA2 mutation carriers: effects of oral contraceptive use and parental origin of mutation.

BRCA1 and BRCA2 germline mutations substantially increase breast and ovarian cancer risk, yet penetrance is incomplete. The effects of oral contraceptives (OC) on breast cancer risk in mutation carriers are unclear, and the putative effect of parental origin of mutation on cancer risk has not been reported. Data on OC use and parental origin of the mutation were obtained at counseling from 888 BRCA1 (n = 638) or BRCA2 (n = 250) Jewish Israeli mutation carriers who were counseled and genotyped in a single medical center.