Value of gamma-glutamyltransferase in the diagnosis of liver metastases.

Gamma-glutamyltransferase (gamma-GT) was found to exceed the upper normal limit in 31 of the 32 patients with liver metastases verified during surgery or at autopsy, while the level of this enzyme was normal in 25 of the 28 patients with proven neoplasma but without evidence of metastatic involvement of the liver. Particularly high values of gamma-GT activity were noted in 9 patients in whom liver metastases were accompanied by clinical jaundice. A similar behaviour was noted for alkaline phosphatase but changes affecting this enzyme were less obvious. Thus, for a mean increase of gamma-GT to levels up to seven times the upper normal limit, the level of alkaline phosphatase increased only three times. A decrease of serum pseudocholinesterase occurred in most patients with neoplasma, the process being more evident when liver metastases were present. It is concluded that an increase of gamma-GT in a patient with neoplasma could be considered as a marker of hepatic metastases, if chronic alcoholism or hepatobiliary disease can be excluded.