Locally advanced undifferentiated carcinoma with osteoclast-like giant cells of the pancreas.

Undifferentiated carcinoma with osteoclast-like giant cells of the pancreas (UCOGCP) is an unusual pancreatic neoplasm that represents < 1% of all pancreatic malignancies. Moreover, the giant cells of UCOGCP morphologically resemble the benign giant cells of bone tumors. Due to the rarity of this tumor type, the histogenesis and biologic behavior of UCOGCP remain controversial. Here, we report a case of UCOGCP that exhibited an invasive growth pattern involving infiltration of the adjacent bowel loop and portal vein, as well as superior mesenteric vein thrombosis. The patient underwent a distal pancreatectomy with splenectomy and partial colectomy, followed by four cycles of gemcitabine chemotherapy. No evidence of recurrence was detected after ten years. In addition to this case, clinical information on other UCOGCP cases reported in the English literature is summarized.