The Systemic Immune-Inflammation Index Predicts Portal Vein Tumor Thrombosis and Informs a Clinical Nomogram in HBV-Related Hepatocellular Carcinoma

BackgroundThis study aims to investigate the potential association between the incidence of portal vein tumor thrombosis (PVTT) and a panel of inflammatory indices-namely the systemic immune-inflammatory index (SII), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR)-in patients with HBV-related hepatocellular carcinoma (HCC).MethodsCovariates were identified through univariate and multivariate logistic regression analyses alongside the variance inflation factor (VIF). The associations of inflammatory biomarkers were evaluated using subgroup analyses, multivariate logistic regression, and restricted cubic spline (RCS) models. A nomogram was developed based on the selected variables, and calibration curves were plotted to assess the predictive accuracy of the model. Receiver operating characteristic (ROC) curves were generated, and the area under the curve (AUC) was calculated to evaluate the diagnostic performance of the model.ResultsIn this study of 504 HBV-related HCC patients, PVTT was identified in 22.02% of cases. Multivariate analysis confirmed SII and PLR as independent risk factors for PVTT, with the third quartile of SII and PLR associated with 109.7% and 122.6% increased risk, respectively. A nonlinear dose-response relationship for SII was identified with an inflection point at 467.5. A nomogram incorporating SII and five clinical variables demonstrated good predictive accuracy (AUC = 0.760) and high specificity (84%), supporting its utility for clinical risk stratification.ConclusionsThe SII was identified as an independent risk factor for PVTT in patients with HBV-related HCC.