Prevalence of <i>BRCA1</i> and <i>BRCA2</i> Germline Mutations in Vietnamese Patients With Triple-Negative Breast Cancer

IntroductionTriple-negative breast cancer (TNBC) represents approximately 10-20% of all breast cancer cases and is frequently associated with <i>BRCA1</i> mutations. Numerous studies from Western populations have investigated the prevalence of germline <i>BRCA</i> mutations in individuals with TNBC; however, the prevalence of <i>BRCA1/2</i> mutations in TNBC patients varies widely between countries and from study to study. Evidence from Asian populations, particularly Vietnamese patients, remains limited. In this study, we determined the prevalence of germline <i>BRCA1/2</i> mutations among unselected Vietnamese patients with TNBC and analyzed the clinicopathological features.MethodsWe conducted a single-center retrospective study of 68 women diagnosed with TNBC at the Vietnam National Cancer Hospital. Germline <i>BRCA1</i>/<i>2</i> testing was performed by next-generation sequencing.ResultsOverall, 19 Vietnamese patients (27.9%) had <i>BRCA1/2</i> mutations, with 14 (20.6%) in <i>BRCA1</i> and 5 (7.4%) in <i>BRCA2</i>. Three patients (4.4%) had variants of uncertain significance (2 <i>BRCA1</i> mutations and 1 <i>BRCA2</i> mutation). Thirteen distinct pathogenic or likely pathogenic variants (8 <i>BRCA1</i> and 5 <i>BRCA2</i>) were found. Among patients diagnosed at ≤60 years, the prevalence of <i>BRCA1/2</i> mutations was 32.0%. The average age at diagnosis for <i>BRCA1/2</i> mutation carriers was notably lower than that observed in non-carriers (43.1 vs 51.7 years, <i>P</i> = .021). <i>BRCA1/2</i> mutation carriers were also more frequently premenopausal (78.6% vs 43.9%, <i>P</i> = .025).ConclusionsThere is a high prevalence of <i>BRCA1/2</i> mutations among TNBC patients in Vietnam. Women with TNBC in Vietnam should be screened for mutations in <i>BRCA1/2</i>.