Value of combined model of clinical and imaging based on dual-energy CT for differentiating benign and malignant portal vein embolus

To investigate the value of dual-energy CT (DECT) quantitative parameters combined with clinical laboratory indicators in differentiation of portal vein tumor thrombus (PVTT) from thrombosis (PVT).

A case-control study was conducted on 65 patients diagnosed with portal vein thrombosis (n=39) or tumor embolus (n=26) who underwent abdominal dual-energy enhanced CT examination in our department from May 2022 to March 2024. Their clinical and imaging data were collected. Linear blending image (LB), non-linear blending image (NLB), 40 keV and 100 keV virtual monoenergetic image (VMI), iodine image and electron density/effective atomic number image (Rho/Zeff) were reconstructed with the aid of post-processing workstation. The image characteristics of thrombus were evaluated in LB images, including whether the vessel wall at the thrombus was smooth, whether the vessel at the thrombus was widen, and whether the embolus was neovascularization. The quantitative parameters and clinical laboratory indicators of PVT and PVTT in DECT were compared. Laboratory indicators included apha-fetoprotein (AFP), carcinoembryonic antigen (CEA), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Univariate and multivariate logistic regression analyses were employed to analyze DECT quantitative parameters, embolus image characteristics and clinical laboratory indicators. Then receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic efficiency of the quantitative parameters and combined model of DECT.

Among the DECT parameters, except for Rho, the other parameters in PVTT were significantly higher than those in PVT (P < 0.05). Multivariate logistic regression analysis showed that there were obvious differences in LB, NLB, CEA and AST (P < 0.05), and NLB had better diagnostic efficacy (AUC: 0.830, sensitivity: 53.85%, specificity: 100.00%, accuracy: 81.54%). The combined model based on DECT quantitative parameters and clinical laboratory indicators (LB+NLB+CEA+AST) obtained the best diagnostic efficacy (AUC: 0.983, sensitivity: 96.15%, specificity: 92.31%, accuracy: 93.85%).

The combined imaging and clinical model based on DECT provides a reliable reference for the differential diagnosis of benign and malignant portal vein embolus, and it has potential application prospects.