Patterns and the Occurrence of KRAS Mutations in Metastatic Colorectal Cancers-a Study from Indian Regional Cancer Centre.

Mutation analysis of the KRAS oncogene is established as a predictive biomarker in Colorectal cancer (CRC). Many prospective clinical trials have shown that only CRCs with wild-type KRAS respond to anti-epidermal growth factor receptor (EGFR) treatment. Hence, mutation analysis is mandatory before treatment of metastatic CRCs. There are very few studies on the KRAS mutation status in the Indian setting. Hence, this study was done to document the patterns of KRAS mutations in CRCs reporting to a regional cancer centre in South India. Among 150 cases of metastatic colorectal cancer reporting over a period of 20 months, 48 random cases were analyzed for the KRAS mutational status of codons 12 and 13 of the KRAS gene by genomic sequencing. KRAS mutations in codons 12 and 13 were present in 9/48 (18.75%) of all analyzed CRCs. The common types of mutations were glycine to aspartate on codon 12 (p.G12D), glycine to valine on codon 12 (p.G12 V), and glycine to aspartate on codon 13 (p.G13D).