Detection of K-ras gene mutations in bile and bile duct brushings for diagnosis of cholangiocarcinamas

Objective To explore the value of the detection of K-ras gene mutations in bile and bile duct brushings for diagnosis of cholangiocarcinamas.Methods PCR-SSCP and DNA sequencing were performed to detect K-ras gene mutations in bile (n=23),bile duct brushings (n=14) and bile duct cancer tissues (n=10).Results K-ras gene mutations in bile,bile duct brushings and bile duct cancer tissues were found in 54.6%,60.0% and 60.0% of patients with cholangiocarcinamas respectively,but no mutation was observed in benign bile duct disease.Using DNA sequencing analysis,point mutations were detected in 2 patients and insertion mutations in 4 patients with cholangiocarcinamas.K-ras gene mutations and its types discovered from bile,bile duct brushings and bile duct cancer tissues of the same patient were identical.Conclusion The detection of K-ras gene mutations in bile and bile duct brushings may be useful for preoperative diagnosis of cholangiocarcinamas.