Intrahepatic biliary cystadenoma mimicking hydatid cyst of liver: A clinicopathologic study of six cases

Background: Intrahepatic biliary cystadenomas are rare hepatic neoplasms, which are usually cystic. These tumors are often misdiagnosed as simple liver cysts and hydatid cysts clinically and radiologically owing to nonspecific clinical and radiologic features. These tumors require complete resection, as recurrence and malignant transformation can occur following incomplete excision. It is essential that these tumors be diagnosed accurately so that they can be adequately excised. Methods: Clinical and radiological features of six cases of biliary cystadenoma are described. Results: All of these cases were resected with the clinical and/or radiological impression of simple liver cysts and/or hydatid cysts. Out of the six patients, five were female and one was male. Ages of the patients ranged from 28 to 60 years (mean 45 years). The patients presented with nonspecific symptoms. Internal septations were seen on preoperative imaging (when available). On gross examination, all tumors were cystic; their sizes varied from 5.5 to 14 cm, mean size was 9.0 cm. On histopathologic examination, cystic spaces were lined by cuboidal to columnar mucin-secreting epithelium with underlying ovarian-type stroma. In one case, ovarian-type stroma was not seen. Recurrence was seen in three cases at 1 to 5 years of follow up. Conclusions: Owing to their malignant potential and high recurrence rate following incomplete resection, an aggressive surgical approach is recommended. Prognosis is excellent after complete resection.