Serum monomeric laminin‐γ2 as a novel biomarker for hepatocellular carcinoma

The diagnosis of hepatocellular carcinoma (HCC) in the early stages is important for successful clinical management. Laminin (Ln)‐γ2 expression has been reported in various types of malignant carcinomas. We recently developed a highly sensitive method to measure serum monomeric Ln‐γ2 levels using a fully automated chemiluminescent immunoassay (CLIA). Using our CLIA, we evaluated its diagnostic value in sera from patients with chronic liver disease (CLD) and patients with hepatocellular carcinoma (HCC). Serum alpha‐fetoprotein (AFP) and des‐gamma‐carboxy prothrombin (DCP) were also examined in these subjects. Median levels of Ln‐γ2 were significantly higher in patients with HCC (173.2 pg/mL; range: 39.5–986 pg/mL) compared with patients with CLD (76.7 pg/mL; range: 38.7–215.9 pg/mL) and with healthy volunteers (41.1 pg/mL; range: 10.9–79.0 pg/mL). The optimal cutoff value for Ln‐γ2 that allowed us to distinguish between HCC and nonmalignant CLD was 116.6 pg/mL. Elevated Ln‐γ2 levels were observed in 0% of healthy volunteers, 17% of patients with CLD, and 63% of patients with HCC. The positivity rate in patients with HCC for the combination of Ln‐γ2 and DCP was 89.5%, which was better than that for either of the two markers alone (63% and 68%, respectively). Among patients with early‐stage HCC (T1 or T2), the positivity rates for monomeric Ln‐γ2, AFP and DCP were 61%, 39% and 57%, respectively. Serum Ln‐γ2 may be a potential biomarker for HCC surveillance. The combination of Ln‐γ2 and DCP may be more sensitive for laboratory diagnosis of HCC than the combination of AFP and DCP.