Prognostic significance of K-ras codon 12 mutation in patients with resected gallbladder cancer.

Background: Point mutation of K-ras is associated with carcinogenesis and overall survival in various cancers. We investigated the mutational spectrum of K-ras codon 12 in resected normal and gallbladder cancer tissue samples in a Northern Indian population and correlated it with different clinicopathological parameters. Patients and Methods: Gallbladder tissues from normal (n = 24) and cancer patients (n = 39) were analyzed for K-ras codon 12 mutation by restriction fragment length polymorphism. Statistical analysis was carried out using the χ2 test or Fisher's exact test. Survival was estimated using the Kaplan-Meier method, and the difference between survival curves was analyzed by the log-rank test. Results: The frequency of K-ras mutation was significantly higher (p = 0.001) in gallbladder cancer tissue samples (16/39) compared to normal samples (1/24). Patients with K-ras mutation had a significantly decreased overall survival (p = 0.003), particularly for stage II (p = 0.021) and III (p = 0.009) cancers. No significant correlation was observed with any of the other clinicopathological factors studied. Conclusions: Gallbladder cancer has a high frequency of K-ras codon 12 mutation with poorer outcomes in resected stage II and III disease. K-ras mutational analysis has important prognostic implications that need to be investigated further.