Novel gamma-GTP isoenzyme as diagnostic tool for hepatocellular carcinoma.

Out of 13 bands of gamma-GTP isoenzymes which were separated by our method, band II, II' and I' were specifically found in sera of patients with hepatocellular carcinoma (HCC), and therefore were called HCC specific novel gamma-GTP isoenzyme (novel gamma-GTP). One or more of these bands were detectable in 95 out of 178 patients with HCC. The positive ratio of novel gamma-GTP was 53% in total patients of HCC, and corresponded to 71% in patients whose serum activity of gamma-GTP was more than 100 mu/ml. In general, there was significant correlation between positivity of the novel gamma-GTP and titer of AFP. However, it was found in 33% of patients with AFP levels below 400 ng/ml which were frequently encountered in liver diseases other than HCC. From these results novel gamma-GTP can be useful also in diagnosis of HCC patients in whom serum AFP is lower or negative.