Background: Lens culinaris agglutinin-reactive α-fetoprotein (AFP-L3) and des-γ-carboxy prothrombin (DCP) have been routinely used as serological tumor markers of hepatocellular carcinoma (HCC) for surveillance. The aims of this study were: (i) to determine the biological variation of AFP-L3 and DCP in patients with chronic hepatitis C; and (ii) to calculate the reference change values (RCVs) of AFP-L3 and DCP.
Methods: Ten patients with cirrhosis due to hepatitis C virus (HCV) infection and without HCC were enrolled in the study. Serum samples were collected at 14-day intervals, and 10 samples in total were obtained for each patient. AFP-L3 and DCP levels were measured by microchip capillary electrophoresis and liquid-phase binding assay. Intra-individual (CV(I)) and inter-individual (CV(G)) biological variations and RCVs were estimated from the data generated.
Results: The CV(I) was 29.0% for AFP-L3 and 24.6% for DCP, and CV(G) was 63.5% for AFP-L3 and 40.4% for DCP. The RCVs for AFP-L3 and DCP were 68.3% and 58.5%, respectively.
Conclusions: Increases in values for AFP-L3 and DCP within 68.3% and 58.5% may be biological variations. Clinician should take these variations into consideration for the management of patients with HCV infection under surveillance of HCC.