粘液性嚢胞性腫瘍が疑われた胆管内嚢胞性腫瘍の1例

A case of cystic neoplasm with intrabiliary growth

肝胆道系発生の粘液性嚢胞性腫瘍（肝mucinous cystic neoplasm：肝MCN）は2010年WHO分類で定義された嚢胞形成性の上皮性腫瘍であり，かつて胆管嚢胞腺腫/胆管嚢胞腺癌と報告されていたものの一部である。

Mucinous cystic neoplasm（MCN）of the liver is a cyst-forming epithelial neoplasm defined in the WHO classification. Here, we present a case of a 51-year-old female with an intrabiliary cystic tumor, in which MCN was the most likely diagnosis. MCN with intrabiliary growth is rare and only about 10％ of liver MCNs involve the extrahepatic bile ducts. The common tumor location（left lobe）, presence of septations in the tumor, and the oval-shaped filling defect can be the characteristic imaging features.