BACKGROUND: To retrospectively analyze computed tomography (CT) features of adenosquamous carcinoma (ASC) of the extrahepatic bile duct and to correlate them with pathologic findings. METHODS: Six patients who underwent radical surgical resection for ASC of extrahepatic bile duct were included. CT and pathologic findings were analyzed and correlated with each other. RESULTS: Five ASCs were periductal infiltrative type and the remaining one was intraductal polypoid type. Histologically, ASC was composed of squamous and glandular components which mixed in an intermingled pattern and was characterized by a high local aggressiveness mainly due to the squamous component. The most common CT findings were a segmental wall thickening with delayed enhancement. Overall, CT features were well correlated with pathologic findings. However, CT tended to underestimate radial extent of the tumor compared with histologic findings. CONCLUSIONS: Histopathologically, ASC of the extrahepatic bile duct is characterized by greater local aggressiveness. However, their CT findings are not quite different from those of usual adenocarcinoma due to the unique geographic characteristic of being located at a very limited space.
BACKGROUND: To retrospectively analyze computed tomography (CT) features of adenosquamous carcinoma (ASC) of the extrahepatic bile duct and to correlate them with pathologic findings. METHODS: Six patients who underwent radical surgical resection for ASC of extrahepatic bile duct were included. CT and pathologic findings were analyzed and correlated with each other. RESULTS: Five ASCs were periductal infiltrative type and the remaining one was intraductal polypoid type. Histologically, ASC was composed of squamous and glandular components which mixed in an intermingled pattern and was characterized by a high local aggressiveness mainly due to the squamous component. The most common CT findings were a segmental wall thickening with delayed enhancement. Overall, CT features were well correlated with pathologic findings. However, CT tended to underestimate radial extent of the tumor compared with histologic findings. CONCLUSIONS: Histopathologically, ASC of the extrahepatic bile duct is characterized by greater local aggressiveness. However, their CT findings are not quite different from those of usual adenocarcinoma due to the unique geographic characteristic of being located at a very limited space.