Cystadenoma of the liver treated by hepatic resection

The aim of this study is to report a case of cystadenoma in the liver and to discuss the difficulty of differential diagnosis from malignant tumor and the importance of complete resection of the lesion. The patient had epigastric pain and abdominal distension. Hepatic ultrasonography, abdominal CT, magnetic resonance imaging, and angiography showed the presence of a large cystic tumor occupying the right hepatic lobe indicating malignant cystadenocarcinoma. Needle biopsy of the cyst wall with sampling of the cyst fluid was performed, which revealed no malignant cells. However, CEA and CA19-9 were markedly elevated in the cyst fluid. A right trisegmentectomy via laparotomy was performed successfully. The resected tumor was 11.5x9x9 cm in size and weighed 1,240 g. The cut surface revealed the tumor with multiple cysts, in some parts of which large papillary projections into lumina were seen. Though the gross features were similar to those of cystadenocarcinoma, the final histological diagnosis was benign cystadenoma of the liver. The postoperative course was uneventful, and the patient is in good condition six years postoperatively without evidence of recurrence of the disease.