Cholangiolocellular carcinoma with rapid progression initially showing abnormally elevated serum alfa-fetoprotein.

Cholangiolocellular carcinoma (CoCC) is a rare malignant liver tumor derived from hepatic progenitor cells, which exist in the canals of Hering. We encountered a case of CoCC with an extremely poor clinical course, initially showing abnormally elevated serum alfa-fetoprotein (AFP). A 72-year-old male presented with a liver tumor and abnormally elevated serum AFP levels (16,399 ng/ml). We preoperatively diagnosed hepatocellular carcinoma and performed extended right hepatectomy, after which the serum AFP levels remarkably decreased to 97 ng/ml. Postoperatively, the disease was pathologically diagnosed as CoCC. Furthermore, immunohistochemical pathological findings were alcian blue negative, cytokeratin (CK) 7 partially positive, CK19 positive, hepatocyte paraffin-1 negative, membranous negative for epithelial membrane antigen, and AFP negative. Fifty-five days later, intra- and extrahepatic recurrence developed, and the patient died 65 days after surgery. Although CoCCs show favorable outcomes, these characteristics of our case were not previously reported. It is necessary to accumulate more information on CoCC.