Surgical treatment of the pancreatic cancer is currently unsatisfactory. By using anti-K,H,N-ras monoclonal and anti-myc polyclonal antibodies, paraffin-embedded tissue specimens of the carcinoma in digestive organs were immunohistologically studied. Then, the incidence of expression of these oncogenes and correlative studies of survival rate and disease stage of pancreatic cancer were analyzed. High incidence of expression of ras oncogene in the carcinoma of the pancreas and biliary tract was obtained. Frequency of expression of ras oncogene was correlated to disease stage and T factor for staging the carcinoma of the pancreas. Prognoses of 6 cases of pancreatic cancer without expression of ras oncogene were better than that of pancreatic cancer expressed ras oncogene.