Prevalence of <i>BRCA1</i> and <i>BRCA2</i> Mutations Among Patients With Ovarian, Primary Peritoneal, and Fallopian Tube Cancer in India: A Multicenter Cross-Sectional Study.

Abstract

There are deficient data on prevalence of germline mutations in breast cancer susceptibility genes 1 and 2 (<i>BRCA1</i>/<i>BRCA2</i>) in Indian patients with ovarian cancer who are not selected by clinical features. This prospective, cross-sectional, noninterventional study in nine Indian centers included patients with newly diagnosed or relapsed epithelial ovarian, primary peritoneal, or fallopian tube cancer. The primary objective was to assess the prevalence of <i>BRCA1</i>/<i>BRCA2</i> mutations, and the secondary objective was to correlate <i>BRCA1</i>/<i>BRCA2</i> status with clinicopathologic characteristics. Mutation testing was performed by a standard next-generation sequencing assay. Between March 2018 and December 2018, 239 patients with a median age of 53.0 (range, 23.0-86.0 years) years were included, of whom 203 (84.9%) had newly diagnosed disease, 36 (15.1%) had family history of ovarian or breast cancer, and 159 (66.5%) had serous subtype of epithelial ovarian cancer. Germline pathogenic or likely pathogenic mutations in <i>BRCA1</i> and <i>BRCA2</i> were detected in 37 (15.5%; 95% CI, 11.1 to 20.7) and 14 (5.9%; 95% CI, 3.2 to 9.6) patients, respectively, whereas variants of uncertain significance in these genes were seen in four (1.7%; 95% CI, 0.5 to 4.2) and six (2.5%; 95% CI, 0.9 to 5.4) patients, respectively. The prevalence of pathogenic or likely pathogenic <i>BRCA</i> mutations in patients with serous versus nonserous tumors, with versus without relevant family history, and ≤ 50 years versus > 50 years, were 40 of 159 (25.2%; 95% CI, 18.6 to 32.6) versus 11 of 80 (13.8%; 95% CI, 7.1 to 23.3; <i>P</i> = .0636), 20 of 36 (55.6%; 95% CI, 38.1 to 72.1) versus 41 of 203 (20.2%; 95% CI, 14.9 to 26.4; <i>P</i> < .0001), and 20 of 90 (22.2%; 95% CI, 14.1 to 32.2) versus 31 of 149 (20.8%; 95% CI, 14.6 to 28.2; <i>P</i> = .7956), respectively. There is a high prevalence of pathogenic or likely pathogenic germline <i>BRCA</i> mutations in Indian patients with ovarian cancer.