Abstract

The hypothesis that an increased rate of oxidative metabolism may be an initiator or promoter of hepatocellular carcinoma was tested in vivo. Elimination of antipyrine (phenazone) was used as an index of the activity of microsomal mixed function oxidative enzymes. Plasma antipyrine kinetics were examined in 10 patients with hepatocellular carcinoma and in 10 normal Sudanese adults. The half life, volume of distribution and clearance of antipyrine in patients were 18.8 +/- 7.9 hours (mean +/- SD), 33.8 +/- 7.7 litres and 23.7 +/- 10.1 ml/min, respectively; and in normal adults were 20.3 +/- 8.8 hours, 40.1 +/- 10.4 litres and 25.7 +/- 12.0 ml/min, respectively. These differences were not significant. Antipyrine plasma clearance when corrected for weight was similar in the two groups. This study suggests that in a population at risk for hepatocellular carcinoma, the overall activity of mixed function oxidative enzymes is not an important determinant in selectively increasing this risk.