K-RAS STATUS DOES NOT PREDICT SUCCESSFUL HEPATIC RESECTION OF COLORECTAL-CANCER METASTASIS

Objective: To establish whether specific K-ras alterations are predict ive of less aggressive turner behavior and subsequently those patients who are most likely to benefit from resection of hepatic metastases f rom colorectal carcinoma. Design: Evaluation of long-term survivors of hepatic resection for metastases of colorectal carcinoma (median surv ival, 85 months). Results: DNA, extracted from 26 paraffin-embedded he patic metastases from 19 patients, was analyzed using single-strand co nformation polymorphism and direct sequence analysis of codons 12 and 13 of the K-ras gene. Seven of 19 patients were found to harbor K-uas mutations. A similar frequency and spectrum of K-uas mutational events was detected in 14 patients with shortterm survival following patholo gic diagnosis of hepatic metastasis. Conclusions: Neither the presence of a K-vas mutational event nor the precise nucleotide change are pre dictive of less aggressive tumor behavior, and genetic alterations at this locus alone cannot be used to select patients undergoing resectio n of hepatic metastases from colorectal carcinoma.