Significance of the Detection of Ki-ras Codon 12 Mutation in the Diagnosis and Differential Diagnosis of Pancreatic Carcinoma

Ki-ras codon 12 mutation was detected in: (1) surgically resected formalin-fixed and paraffin-embedded specimens from 109 carcinoma cases, including 46 pancreatic, 35 ampullary, 24 extrahepatic bile duct, and 4 gallbladder carcinomas, showing prevalences of 95.7%, 5.7%, 8.3%, and 0%, respectively, by polymerase chain reaction-restriction fragment length polymorphism technique, and 89.1%, 2.9%, 8.3%, and 0%, respectively, by polymerase chain reaction-dot blot method; and (2) 35 consecutive fine-needle aspiration biopsy specimens by polymerase chain reaction-restriction fragment length polymorphism giving a positive rate of 94.7% (18/19) for pancreatic carcinoma and 0% (0/16) in the specimens from nonpancreatic carcinoma tissues or tumors. Our results demonstrate that the strikingly high prevalence of Ki-ras codon 12 mutation of pancreatic carcinoma could be used as an effective means in the diagnosis and differential diagnosis of pancreatic carcinoma.