Multicenter cross-sectional screening of the BRCA gene for Chinese high hereditary risk breast cancer populations.

Due to lack of systematic reviews, BRCA, DNA Repair Associated (BRCA) mutations in the Chinese population are not completely understood. The following study investigates the prevalence and type of BRCA mutations in Chinese patients with high hereditary risk of breast cancer (BC). Patients Drwere recruited from 14 cities between October 2015 and February 2016, and were selected based on family and personal medical history. BRCA mutations were analyzed by collecting blood samples from all participants. 437 BC patients were included. A total of seventy-six (17.4%) mutation carriers were identified with no geographic difference. The mutation rate in the early-onset BC patients was lower compared to family history of breast/ovarian cancer (OC), bilateral BC, male BC, BC&OC or meeting ≥2 criteria (9.2 vs. 21.7, 24.0, 22.2, 16.7 and 24.3%, respectively, P=0.007). A total of 61 mutation sites were identified (BRCA1 32, BRCA2 29) including 47.5% novel sites and extra 10 variants of uncertain significance. A total of five sites were repeated in more than one unrelated patient. A total of 11 sites were associated with hereditary breast and ovarian cancer syndrome, two of which were confirmed by family pedigrees. Compared with BRCA- patients, patients with BRCA1 mutation tended to be triple-negative BC (P<0.001), whereas patients with BRCA2 mutation were more likely to be hormone receptor positive BC (P=0.02). The present study provides a general BRCA mutation profile in the Chinese population. The prevalence of BRCA mutation in BC patients with high hereditary risk is lower compared with Western populations. Chinese mutation type is different with Western people, without obvious founder mutation.