Mutación del gen K-ras en el cáncer de la vesícula biliar K-ras gene mutation in gallbladder carcinoma

Background: Different K-ras mutation frequencies in gallbladder cancer have been reported. Aim: To study the frequency of K-ras gene mutations in advanced gallbladder carcinoma not associated to anomalous junction of pancreatic-biliary duct (AJPBD). Material and methods: 33 formalin fixed paraffin embedded samples of gallbladder carcinoma (30 women, age range 32-86 years) were selected. Pancreatic cancer tissue with K-ras mutations was used as control. DNA was extracted from the histological section by mean of microdissection and K-ras mutations in codon 12 were detected by polymerase chain reaction and restriction fragment length polymorphism (RFLP), using previously reported technique. Results: Most cases were poorly differentiated adenocarcinomas. K-ras mutation was detected in 10 cases (30%) samples. No differences in K-ras mutation frequency between subserous and serous tumors were detected and no relation between histological features and the mutation was observed. Conclusions: K-ras mutation in codon 12 is present in 30% in our advanced gallbladder carcinomas. The study of K-ras mutation in preneoplastic lesions and early carcinomas will be important to determine the role of this gene in the gallbladder carcinogenesis in Chile (Rev Méd Chile 2004; 132: 955-60)