ABSTRACT
BACKGROUND: Activating mutations of the oncogene K-RAS are a common finding within cells of malignant, sporadic colorectal cancer. The existence of such mutations endows the tumor with proliferation potential which is independent of external stimuli by growth factors such as the epidermal growth factor of upstream receptor (EGFR]. Hence, anticancer, novel biologic drugs, aimed at inhibiting the EGFR, such as cetuximab, are rendered ineffective in cases of colorectal cancer harboring activated K-RAS. AIMS: Quantification and characterization of activating mutations in a large cohort of sporadic colorectal tumors in the Israeli population. METHODS: The results of a mutation analysis kit application in 419 tumor samples collected in Israel during the years 2007-2009 by the diagnostic unit of Teva in Israel--Oncotest-Advantest Ltd. RESULTS: The utilization of a direct, pre-specified mutation kit analysis (TheraScreen: K-ras Mutation Kit) has identified a total rate of 44.8% mutations. Most mutations (82.4%) were identified within codon 12 and the minority on codon 13. These results are in concordance with modern series conducted worldwide.
