Abstract
BACKGROUND: Differentiating bland from neoplastic portal vein thrombosis (PVT) is crucial for staging and treatment decisions in patients with suspected or confirmed liver malignancies. This study aimed to assess the diagnostic efficacy of the quantitative parameters of dual-layer spectral detector computed tomography (DLCT) in distinguishing between bland and neoplastic PVT. METHODS: This single-center prospective study included consecutive patients with identifiable PVT who underwent contrast-enhanced liver DLCT between April 2022 and August 2023. The reference standard was established based on imaging, patient history, and follow-up data. Quantitative parameters, including computed tomography (CT) attenuation values from conventional and virtual monoenergetic (40-90 keV) images, iodine density, effective atomic number (Zeff), and arterial enhancement fraction (AEF), were documented. Interobserver agreement was assessed via the intraclass correlation coefficient (ICC). A combined score integrating DLCT quantitative parameters was developed, and diagnostic performance was evaluated according to the area under the receiver operating characteristic (ROC) curve (AUC), sensitivity, and specificity. RESULTS: A total of 81 patients (median age 54 years; 64 males) were enrolled, including 31 patients with bland PVT and 50 with neoplastic PVT. Baseline characteristics showed significant differences between the bland PVT and neoplastic PVT groups, including in α-fetoprotein (AFP) level (median 3.3 vs. 932.0 ng/mL, P<0.001), aspartate aminotransferase (AST) level (median 40.0 vs. 68.5 U/L, P=0.004), and PVT diameter (mean 13.6 vs. 16.5 mm, P=0.02). The quantitative DLCT parameters were significantly different between the bland and neoplastic groups (all P values ≤0.001). Interobserver agreement was good to excellent (ICC 0.796-0.973). Quantitative parameters from the arterial phase, as compared to those from the portal venous phase, exhibited higher diagnostic AUC values and specificity, but lower sensitivity for neoplastic PVT. The CT attenuation values of arterial-phase 40-keV virtual monoenergetic images achieved the highest AUC of 0.938 [95% confidence interval (CI): 0.862-0.980], with a sensitivity of 84.0% and a specificity of 96.8%. The AEF also showed high diagnostic performance, with an AUC of 0.930 (95% CI: 0.851-0.975), a sensitivity of 90.0%, and a specificity of 93.6%. The combined score derived from the arterial-phase DLCT quantitative parameters and AEF achieved the highest AUC of 0.979 (95% CI: 0.919-0.998) for diagnosing neoplastic PVT, with a sensitivity and specificity of 94.0% and 100.0%, respectively. CONCLUSIONS: DLCT quantitative parameters effectively distinguished between bland and neoplastic PVT. The combined score derived from quantitative DLCT parameters demonstrated superior diagnostic performance, potentially aiding in accurate staging and treatment decisions for patients with suspected or confirmed liver malignancies. Further large-scale multicenter studies are needed to confirm these findings.