Evaluation of KRAS and NRAS mutations in metastatic colorectal cancer: an 8-year study of 10 754 patients in Turkey.

This study aimed to evaluate KRAS and NRAS mutations over an eight-year period to provide a comprehensive understanding of the genetic landscape of metastatic colorectal cancer (mCRC) in Turkish patients. Tumor tissue samples were collected from 10 754 patients with mCRC between January 2015 and June 2023 from multiple centers across Turkey, and all genetic analyses were performed at a single facility. DNA was analyzed for mutations in codons 12, 13, 59, 61, 117, and 146 of the KRAS and NRAS genes using nested PCR and multiplex minisequencing techniques. Among the conclusive results from 10 681 patients, 46.6% (4982) had KRAS mutations, and 53.4% (5699) were wild-type. The most common KRAS mutations were G12D (30.3%), G12V (20.1%), G13D (18.4%), and G12C (7.0%). Results from the 5699 KRAS wild-type patients revealed that 480 (8.5%) had NRAS mutations, while 91.5% were NRAS wild-type. The most frequent NRAS mutations were Q61K (19.7%), G12D (19.1%), and G12V (12%). This study provides a large-scale, real-world dataset of KRAS and NRAS mutation profiles in Turkish mCRC patients, contributing significantly to the understanding of the genetic characteristics of mCRC in this population.