osteoclast-like giant cell tumor（OGCT）of the liverの1剖検例

: A 57-year-old man presented with jaundice. Abdominal computed tomography showed a 10-cm left hepatic lobe heterogeneous solid mass with low attenuated areas in the mass, multiple liver metastases and lung metastasis. Serology for hepatitis B and C were negative. Serum alpha-fetoprotein, CEA and CA19-9 were normal. The patient died a few weeks later of progressive liver failure and an autopsy was performed. Histologically, the tumor consisted of sarcomatoid mononuclear cells and osteoclast-like giant cells. The liver tissue surrounding the tumor showed no cirrhotic pattern. The osteoclast-like giant cells were uniformly and strongly immunoreactive with CD68. The mononuclear cells demonstrated expression of vimentin but were negative for CAM5.2. The MIB-1 index was 20% for the mononuclear cells. In conclusion, the histopathological diagnosis revealed an osteoclast-like giant cell tumor of the liver.