Enzyme pathology of the liver in patients with and without nonhepatic cancer

Preliminary studies of 13 enzymes subserving various metabolic pathways were undertaken in tumor‐free liver biopsy samples from cancer patients and control subjects. The observations indicate that as a result of nonhepatic neoplasms, with (7 cases) or without (6 cases) hepatic involvement, the biochemical composition of the liver becomes partially undifferentiated. Quantification of appropriate enzymes in histologically normal liver samples could thus distinguish clearly between cancer hosts and controls. The best discriminators include two hepatic enzymes whose concentrations were decreased to less than 30% of normal (soluble glutamate dehydrogenase and the cold stable pyrroline‐5‐carboxylate reductase) and three for which it was elevated two to four‐fold (hexokinase, peptidyl proline hydroxylase and thymidine kinase) in response to distant neoplasms. The same alterations in hepatic enzyme pattern were not seen in any cancer‐free patients with or without morphologic liver damage.