Clinicopathological Features of BRCA1/2 Mutation-Positive Breast Cancer

Abstract

<b><i>Purpose:</i></b> The <i>BRCA1/2</i> gene is the most well-known and studied gene associated with hereditary breast cancer. <i>BRCA1/2</i> genetic testing is widely performed in high-risk patients of hereditary breast cancer in Korea. This study aimed to investigate the clinicopathological characteristics of <i>BRCA1/2</i> mutation-positive breast cancer patients. <b><i>Methods:</i></b> The clinical data of 188 Korean breast cancer patients who underwent genetic testing of <i>BRCA1/2</i> mutation between March 2015 and February 2020 at Pusan National University Yangsan Hospital were retrospectively reviewed. The characteristics of breast cancer according to the expression of <i>BRCA1</i> and <i>BRCA2</i> mutations were analyzed using the Health Insurance Review and Assessment Service guideline criteria and other clinicopathological factors. <b><i>Results:</i></b> The factor associated with <i>BRCA1/2</i> gene expression was cancer stage, and mutation expression was significantly decreased in stage I compared to stage 0 (<i>p</i> = 0.033; odds ratio [OR], 0.169; 95% confidence interval [CI], 0.033–0.867), and there was a tendency to increase in stage II (<i>p</i> = 0.780; OR, 1.150; 95% CI, 0.432–3.064). <i>BRCA1</i> was significantly associated with triple-negative breast cancer (TNBC) (<i>p</i> = 0.004; OR, 5.887; 95% CI, 1.778–19.498). Gene expression of <i>BRCA2</i> was significantly reduced under 40 years of age (<i>p</i> = 0.040; OR, 0.198; 95% CI, 0.042–0.930). There was no difference in disease-free survival (<i>p</i> = 0.900) and overall survival (<i>p</i> = 0.733) between the <i>BRCA1/2</i> mutation-positive and -negative groups. <b><i>Conclusion:</i></b> In this study, the clinicopathological characteristics of breast cancer patients with <i>BRCA1/2</i> gene mutations were identified. <i>BRCA1</i> gene expression was highly correlated with TNBC. <i>BRCA1/2</i> mutation did not have a poor prognosis regarding recurrence and death.