血浆k-ras基因突变检测对胆道系统癌的诊断意义

Incidence and clinical significance of k-ras mutation in plasma of patients with biliary carcinoma

探讨胆道系统癌患者外周血中是否存在ｋ－ｒａｓ基因突变及其诊断价值。方法 提取血浆DNA，通过ｍｕｔａｎｔ ａｌｌｅｌｅ ｓｐｅｃｉｆｉｃ ａｍｐｌｉｆｉｃａｔｉｏｎ（ＭＡＳＡ）方法检测ｋ－ｒａｓ基因codon １２突变。结果 7例胆囊癌中5例ｋ－ｒａｓ基因突变阳性（１７．４％），６例肝内胆管细胞癌和3例总胆管癌中分别有2例（３３．３％）及1例（３３．３％)ｋ－ｒａｓ基因突变检测阳性。ｋ－ｒａｓ基因突变检测阳性而血清CA１９－９、CEA水平均正常者胆囊癌、肝内胆管细胞癌与总胆管癌各1例。结论 胆道系统癌外周血中存在肿瘤DNA，特别是胆囊癌检测血浆ｋ－ｒａｓ基因突变具有较高的诊断意义。

Objective To study whether k-ras mutations can be detected in plasma of patients with biliary cancers and probe into the possibility of developing it as a non-invasive diagnostic marker of biliary cancers.Methods DNA was extracted from plasma,k-ras mutations at codon 12 were determined by using mutant allele specific amplification(MASA) method.Results The incidence of k-ras mutations was 5/7(71.4%),2/6(33.3%),1/3(33.3%)in gallbladder carcinoma,intrahepatic cholangiocellular carcinoma and common duct cancer,respecitively K-ras mutations were not detected in the healthy controls. Conclusion Detection of k-ras mutations in plasma is useful for diagnosis of biliary cancers,especially gall bladder carcinoma.