Prevalence of Germline Pathogenic BRCA mutations in women with High grade Serous ovarian cancers

IntroductionOvarian cancer is the most lethal of all gynaecological malignancies. These malignancies are known to harbour mutations in BRCA genes. Germline mutations in these genes make ovarian cancer more amenable for treatment with poly-ADP ribose phosphate inhibitors (PARPi) as maintenance chemotherapy.BackgroundThe prevalence of BRCA mutations has been found to be higher in women with high grade serous ovarian cancers. However, data regarding prevalence of BRCA mutations in ovarian cancers in the Indian population is scarce.MethodsWomen with a diagnosis of high grade serous ovarian cancers on histopathology were studied for BRCA mutations. Women with other synchronous tumours were excluded. Blood samples from 33 women with high grade serous ovarian cancers were collected, and BRCA mutation analysis was done.ResultsThe total prevalence of BRCA mutations in our study was 33%. BRCA 1 mutations were seen in 19% while BRCA 2 mutations were seen in 18%. Only three of the 11 women with pathogenic mutations had a positive family history of breast or ovarian cancer in first degree relatives. The remaining eight though harbouring deleterious mutations did not have any positive family history. Only one out of the 11 women with pathogenic mutations had a personal history of breast cancer which had been treated a few years prior to the diagnosis of ovarian cancer.ConclusionA positive family history of breast or ovarian cancer, or a personal history of breast cancer alone cannot be used as a criterion for BRCA mutation analysis. Benefits of mutation analysis for the index patient include usage of PARPi for maintenance chemotherapy. For BRCA positive family members, chemoprevention with oral contraceptive pills (OCP), risk reducing surgeries and increased clinical surveillance can be planned.