A Case of a Mucinous Cystic Neoplasm in a Liver-resected Laparoscopic Hepatectomy

Abstract

A 42-year-old woman was referred to our hospital for the evaluation of a cystic lesion in the liver. During physical examination, a hypoechoic mass measuring 23 × 12 mm was detected in the medial segment of the liver using ultrasonography. The patient was followed up for sclerosing hemangioma. Thirty months after the initial diagnosis, the size of the tumor increased to 27 × 18 mm and a cystic lesion with a septum appeared on the dorsal side of the tumor. Laparoscopic partial hepatectomy was performed to diagnose liver mucinous cystic neoplasm (MCN).

Pathological findings showed a columnar epithelium lining the cystic wall and an ovarian-like stromal positive for EgR and PgR with spindle cells. The final diagnosis was an MCN of the liver.

Liver MCN is a rare disease defined as the counterpart of the pancreas according to the WHO 2010 Classification. In our case, the morphological changes observed during follow-up led to the diagnosis of liver MCN ; however, such morphological changes over time remain unclear, as described in previous reports. A liver cyst is not simple, even without typical MCN findings, may change over time, and should be followed up.