Hypercholinesterasemia in patients with hepatocellular carcinoma: a new paraneoplastic syndrome.

Two cases of hepatocellular carcinoma (HCC) were described, in whom hypercholinesterasemia was found. Histochemical examinations revealed that there was a significantly increase in enzyme activity of cholinesterase in liver tissue slice obtained from the part of carcinoma in case 1. It was found that cholinesterase activity in homogenized liver tissue in part of carcinoma was much higher than that of non-carcinoma, and even in other HCC cases, hepatic cirrhosis and control liver tissues. These results suggested that HCC cells were capable of producing cholinesterase and, therefore, that hypercholinesterasemia was an additional paraneoplastic syndrome in HCC.