Sonographic diagnosis of Klatskin tumors.

The sonograms of 14 patients with pathologically proven Klatskin tumors presenting between 1974 and 1985 were reviewed. All 14 patients demonstrated dilated intrahepatic bile ducts with a normal-sized extrahepatic biliary tree. In seven patients this was the only finding. The other seven patients demonstrated one or more additional abnormalities. These included an apparent intraductal mass at the confluence of the right and left intrahepatic ducts (four patients), enlarged portal lymph nodes (two patients), and hepatic metastases (one patient). With one exception, these additional findings were seen only in patients scanned after 1980, that is, using real-time sonography and up-to-date scanners. The presence of dilated intrahepatic ducts in a patient with a normal extrahepatic biliary tree should raise the possibility of Klatskin tumor. With high-resolution real-time sonography, further evidence suggestive of malignancy can be demonstrated in at least 50% of patients.