Background: The aim of the present study was to establish L3 fraction before initial treatment as a useful prognostic factor in a prospective fashion in hepatocellular carcinoma (HCC) where the alpha-fetoprotein (AFP) was very low.
Methods: From 1990 to 2004, 298 HCC patients in whom L3 could be measured were examined in the present study. Enrolled patients with HCC underwent operation, transcatheter arterial chemoembolization and percutaneous ablation therapy. The current patient status was confirmed as of the end of March 2005. L3 was determined by crossed immuno-affinoelectrophoresis when AFP was >/=30 ng/mL. It was carried out by liquid-phase binding assay system on cases where AFP < 30 ng/mL. The tentative discriminating line of L3 was set at 15%.
Results: The HCC group included four subgroups: 110 patients with AFP concentrations </=100 ng/mL, 70 with AFP</= 50 ng/mL, 38 with AFP </= 30 ng/mL and 29 with AFP </= 25 ng/mL. The mean survival rate in the HCC group, whose L3 was >15% (high L3), was significantly lower than that in the HCC group whose L3 was </=15% (low L3). There were also statistically significant differences in survival rates between high and low L3 in the four HCC subgroups. The statistically significant differences were more distinct in the subgroups with low AFP concentrations.
Conclusions: The present study indicates that the L3 fraction before treatment serves as a useful prognostic indicator when the serum concentrations of AFP were very low.