of Cases with a Long Common Channel in the Papilla of Vater High Frequency of K-ras Mutations in Biliary Duct Carcinomas

Abstract The frequency of K-rasmutation in biliary duct carcinomas in differentlocations and the relationship to the form of the junction of the pancre-aticobiliary duct (JPBD) are not understood clearly. These points wereinvestigated in the present study. Thirty-seven biliary duct carcinomas inpatients without anomalous JPBD were investigated for K-ras mutations.Regarding location, 12 were hilar, 4 in the upper, 11 in the middle, and 10in the lower portion of the duct. Furthermore, with 14 cases for which theform of the JPBD could be confirmed by endoscopic retrograde cholan-giopancreatography or postoperative cholangiopancreatography, divisionwas made into two types: those with a long common channel ( > 5 mm) inthe papilla of Vater (type 1, n 5 4), and the other with a shorter ornonapparent common channel (type 2, n 5 10). The overall frequency ofK-rasmutation was 30%, the incidence gradually increasing from upperto lower regions. K-ras mutations were significantly more frequent inbiliary duct carcinomas associated with long common channels (P