BRCA1/2 MUTATION RATE AND CLINICOPATHOLOGICAL CHARACTERISTICS IN PATIENTS WITH BREAST CANCER IN NORTHWEST CHINA

Abstract

Background: Despite the increasing prevalence and importance of BRCA1/2 mutations in breast cancer, there is limited awareness and low adoption of BRCA testing in Northwest China. Therefore, we explored the prevalence of these mutations and the clinicopathological characteristics of patients with breast cancer in this region. Methods: Between January 2021 and August 2023, patients with non-breast and breast cancer were screened for BRCA1/2 mutations at the Department of Nail, Breast, and Vascular Surgery, Xijing Hospital, Air Force Medical University; their family history and clinical data were retrospectively analyzed. Results: The incidence of pathogenic BRCA2 mutations was higher than that of BRCA1 mutations in patients with breast and non-breast cancer. Patients with breast cancer under 45 years had a significantly higher prevalence of BRCA1/2 mutations than those without these mutations, with more number of patients carrying BRCA1 mutations than BRCA2 mutations. Patients with BRCA1/2 mutations had a significantly higher incidence of family history of cancer and a higher proportion of bilateral breast cancer. The proportion of BRCA1 and BRCA2 mutations were significantly higher in grade III tumors and triple-negative breast cancer, respectively. Our findings revealed associations of BRCA1/2 mutations with early-onset breast cancer, family cancer history, bilateral breast cancer, and tumor molecular type. Furthermore, the clinicopathological characteristics of breast cancer differed between patients with BRCA1 mutations and those with BRCA2 mutations. Our results align with those of previous studies in China, suggesting no significant geographic variations. Collectively, we developed a comprehensive database for investigating BRCA1/2 mutations in Northwest China; it may help develop personalized treatment for patients with these mutations.