Gynecologic Oncology

Biography

Biography: Kannan Vaidyanathan

Abstract

Hereditary breast/ovarian cancers are responsible for 5-10% of breast cancers and 7-10% of ovarian cancers. Breast cancer is one of the most common cancers in Indian women. Women carrying BRCA1 or BRCA2 mutations have a lifetime risk of between 60% and 85% for development of breast cancer, and 26% and 54% for development of ovarian cancer for BRCA1, and between 10% and 23% for BRCA2. In this study, 61 breast and/or ovarian cancer patients with a positive family history of breast and/or ovarian cancer were screened for BRCA1/2 mutations. For mutation screening, conformation sensitive gel electrophoresis was used, followed by DNA sequencing, were heteroduplexes were detected. In the BRCA1 gene, 15 mutations were identified; (mutation frequency, 24.6%) and in the BRCA2 gene, two mutations were detected (mutation frequency, 3.28%). Of the BRCA1 mutations identified, 3 were novel mutations and 3 more were previously reported mutations. The mutation, 185delAG was found in 10 patients at a very high frequency of 16.4%. This mutation is detected in high proportion in Ashkenazi Jewish population (18% in breast/ovarian cancers and 1% in general population). A large number of polymorphisms were also detected in BRCA2 gene, which were normal population variants. The mutation spectrum of BRCA1/2 in other Indian studies also indicate a higher incidence of 185delAG mutation, and the important studies shall be reviewed. Haplotype analysis was carried out, and it was found to be different from Ashkenazi Jewish population. The possibility of founder mutation status need to be considered for BRCA1 185delAG mutation.