A new diagnostic method for chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma based on serum metallothionein, copper, and zinc levels

Serum metal levels and their ratios are frequently reported to be good signals for diagnosing various diseases. These parameters are not always specific to the disease, however, it is necessary to use other serum parameters for an exact diagnosis. We examined whether the monitoring of these serum parameters such as metallothionein, copper, and zinc levels are useful in diagnosing hepatic disorders. Metallothionein levels of patients with liver cirrhosis and hepatocellular carcinoma were found to be significantly lower than those of patients with chronic hepatitis and those of controls. In contrast, copper levels of the patients with liver cirrhosis and hepatocellular carcinoma were significantly higher than those with chronic hepatitis and controls. Zinc levels of the patients with chronic hepatitis and hepatocellular carcinoma were lower than those of controls. Using these three parameters, we are introducing a new parameter, (Cu/Zn)/MT, by which we can discriminate between patients in the [control+miscellaneous diseases+chronic hepatitis] group and those in the [liver cirrhosis+hepatocellular carcinoma] group. The new parameter does not, however, allow us to clearly distinguish between the liver cirrhosis and hepatocellular carcinoma groups. Multivariate discriminant analysis was found to be very useful, with combinations of two discriminant functions having been designed to discriminate both between chronic hepatitis and liver cirrhosis and between liver cirrhosis and hepatocellular carcinoma. This method recognizes the differences between hepatic disorder, including chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma groups. On the basis of these results, we propose here that the diagnosis of hepatic disorders should be made based on a combination of three serum levels such as those of metallothionein, copper, and zinc.