Plasma interleukin-17 and alpha-fetoprotein combination effectively predicts imminent hepatocellular carcinoma occurrence in liver cirrhotic patients

Background: Predicting imminent hepatocellular carcinoma (HCC) in liver cirrhotic patients is an unmet medical need. We aimed to investigate circulatory biomarkers and their optimum combinations in a prospective study. Methods: We investigated plasma interleukin 17 (IL-17) concentrations, quantified using enzyme-linked immunosorbent assay (ELISA), for the prediction of HCC in a large cohort of 404 HCC-naïve liver cirrhotic patients regularly followed after recruitment. Additionally, IL-17 in surgically resected tumor tissues were evaluated using immunohistochemistry staining. Results: IL-17 was detected in HCC tissues. The IL-17 concentrations in the peripheral blood do not have correlation with an extensive list of 31 common demographic, metabolic and liver function variables in the cohort of liver cirrhotic patients. Furthermore, patients stratified by IL-17 and alpha-fetoprotein (AFP) showed distinctive cumulative incidence of HCC. Imminent HCC, defined here as HCC occurrence within 1 year, can be predicted by IL-17 alone with an area under the receiver operating characteristic curve [AUC] of 0.762 (P = 0.002). An multivariate analysis showed that age, hepatitis C viral infection, AFP and IL-17 were four independent factors associated with imminent HCC (adjusted P = 0.03, 0.041, 0.024 and 0.008 respectively). An explicit risk score (R) combining the concentrations of two plasma biomarkers, AFP and IL-17, achieved a high AUC of 0.933 (95% confidence interval 0.893–0.972, P < 0.001) in predicting imminent HCC, with 100% sensitivity and 79.9% specificity at the optimum cutoff. The score is defined as: R = (2.6914 ) ∗ IL-17 + (0.3909 ) ∗ AFP - (0.80812875 ) ∗ IL-17 ²+ (0.10288876884 ) ∗ IL-17 ²∗ AFP. Conclusions: The circulatory IL-17 concentration is a predictor of subsequent HCC occurrence in liver cirrhotic patients. The combination of AFP and IL-17 is highly effective in predicting imminent HCC within 1 year.