Cystic duct carcinoma mimicking empyema of the gallbladder.

An 80-year-old woman underwent cholecystectomy because of a clinical and ultrasonic diagnosis of gallbladder empyema. Primary carcinoma of the cystic duct, which was completely removed, was incidentally found during pathologic examination. Although the prognosis following complete removal of this carcinoma is considered to be good, the patient died of the disease 7 months after the operation.