A new study has reported that prior appendectomy is more frequently found in Jewish BRCA mutation carriers with breast and ovarian cancer than in cancer-free mutation carriers. Earlier studies have reported that removal of the appendix might affect cancer risk in the general population. However, to date there is no data on the effect of appendectomy on cancer risk in BRCA1 and BRCA2 carriers.
The study included 677 BRCA1 and 279 BRCA2 mutation carriers, all of whom were Israeli Jewish women counseled in a single medical center. Data concerning appendectomy, cancer type, and age at diagnosis was collected. In addition, data was also collected concerning 225 consecutive non-BRCA carriers with ovarian cancer treated at the same center.
Overall, 367 (38%) of the BRCA mutation carriers had breast cancer (age at diagnosis: 44.1 ± 10.4 years), 142 (15%) had ovarian cancer (53.6 ± 10.1 years), and 438 (46%) were asymptomatic carriers (age at counseling: 41.4 ± 11.2 years). Average age at diagnosis of the non-BRCA ovarian cancer cases was 53.6 ± 10.1 years. Among the mutation carriers, 28/367 (7.6%) breast cancer cases, 15/142 (10.6%) ovarian cancer cases, and 11/438 (2.5%) asymptomatic carriers had undergone prior appendectomy. In all but two women, the appendectomy occurred more than 10 years before the cancer diagnosis or age at counseling. Among the non-BRCA ovarian cancer patients, 12/225 (5.3%) underwent appendectomy, in 10 of whom the appendectomy was performed at least 10 years before the ovarian cancer diagnosis. The authors conclude that prior appendectomy is more frequently found in BRCA1 and BRCA2 carriers with breast and ovarian cancer than in unaffected mutation carriers. The underlying mechanism of action for this association is elusive, and future analyses of ethnically diverse mutation carriers are needed to validate these results.