We found no evidence to support antioxidant supplements for primary or secondary prevention. Beta-carotene and vitamin E seem to increase mortality, and so may higher doses of vitamin A. Antioxidant supplements need to be considered as medicinal products and should undergo sufficient evaluation before marketing.
Pilot clinical trial of the use of alpha-tocopherol for the prevention of hepatocellular carcinoma in patients with liver cirrhosis.
Patients with chronic hepatitis C virus (HCV) infection often develop liver cirrhosis and hepatocellular carcinoma (HCC). The purpose of this study was to test the chemopreventive effect of alpha-tocopherol on hepatocarcinogenesis in patients with liver cirrhosis and a history of HCV infection. Eighty-three patients with liver cirrhosis and with positive history of HCV infection were divided at random into two groups. Forty-four patients were treated with alpha-tocopherol (Vit E group) while the other 39 were followed as controls. The clinical background (gender, age, and laboratory data) was similar in the two groups. Serum levels of alpha-tocopherol, albumin, alanine aminotransferase (ALT), and total cholesterol and platelet count were measured serially over a period of five years. The mean serum concentration of alpha-tocopherol was low in both groups at entry and was significantly higher in the Vit E group than in the control group one month after treatment. Platelet count, serum albumin, ALT, and total cholesterol were not different between the two groups during the five-year period. Cumulative tumor-free survival and cumulative survival rate tended to be higher in the Vit E group than in controls, albeit statistically insignificant. The serum level of alpha-tocopherol was low in patients with liver cirrhosis and positive for HCV. Although the administration of alpha-tocopherol normalized the level one month later, it could neither improve liver function, suppress hepatocarcinogenesis, nor improve cumulative survival. Patients treated with alpha-tocopherol tended to live longer without development of HCC but the difference was not statistically significant.