Importance of cytological examination has been re-ported in the diagnosis of cancer of the duodenum, the hepatobiliary system and the pancreas. Previous reports, however, have been concerned with cytology of duodenal juice obtained during pancreozymin secretin test, that of bile obtained during percutaneous transhepatic cholangiography, or that of bile and pancreatic juice obtained by direct aspiration during operatve laparotomy. Main purpose of our report is to insist on an imp-ortance of cytology of bile and pancreatic juice obtai-ned by aspiration through a cannule inserted into the bile duct and the pancreatic duct at the Vaterian papi ha under the guidance of the duodenof iberscope (Olympus J.F. type B). Followings are the conclusions. (A) Cytological examination of duodenal juice obtained during pancreozymin secretin test gave results similar to those of the previous reports. Drawback of this method is as follows: (1) Inability to pinpoint the site of malignancy when a positive cytology is obtained. (2) False negative result may be obtained when juice is unobtainable due to a complete obstruction of the pancreato-biliary tract by cancer. (3) Degeneration of cells are often advanced and prevent an interpretation of fine cell structures. (4) False negative cytology often results in case of cancer of the tail of the pancreas (3 of 4 cases) and hepatoma (all of 6 cases). (B) Most of the above difficulties can be overcome by the endoscopic aspiration cytology: (1) Degeneration of cells obtained was minimal and fine cell structures were clearly shown. (2) Positive result was obtained even when a complete obstruction of the pancreato-biliary tract was present. (3) Retrograde pancreatoc-holangiography was performed immediately following the endoscopic aspiration cytology. These procedures with endoscopic observation enabled the diagnosis of the site as well as the presence of malignancy of the biliary tract and the pancreas all of 5 cases of ampull-ary cancer, 4 of 5 cases of cancer of the pancreas head and 4 of 5 cases of cancer of the extrahepatic biliary tract. A case of cancer of the extrahepatic biliary y tract which gave a negative cytology was at the proximal end of the common hepatic duct. Malignancy of the intrahepatic biliary tract and the pancreas body and tail was correctly diagnosed by the endoscopic pancre-atocholangiography, but the endoscopic aspiration cytol ogy gave negative results in those cases. In conclusion, the endoscopic aspiration cytology performed simultaneously with an endoscopic observ ation and a retrograde pancreatocholangiography is a method of first choice in the diagnosis of the malign-ancy of the ampulla, the pancreas head, and the biliary tract distal to the common hepatic duct.
