Photon-counting detector CT with iodine quantification: improved distinction between bland and neoplastic portal vein thrombosis
摘要
Neoplastic portal vein thrombosis (PVT) is a critical prognostic factor in hepatocellular carcinoma (HCC); however, differentiation from bland PVT remains challenging using conventional imaging criteria. Photon-counting detector CT (PCD-CT) enables quantitative iodine density (ID) assessment in every contrast-enhanced acquisition. This study evaluated the diagnostic performance of ID for distinguishing bland from neoplastic PVT.
Materials and methodsIn this retrospective single-center study, 104 patients with suspected PVT who underwent PCD-CT between 09/2022 and 08/2024 were included. Based on imaging, follow-up data, and multidisciplinary consensus, patients were classified into four groups: HCC with neoplastic PVT (n = 18), HCC with bland PVT (n = 29), bland PVT without malignancy (n = 31), and neoplastic PVT in non-HCC malignancies (n = 26). ID was measured in the late arterial phase (LAP) and portal venous phase (PVP) by two independent radiologists and compared with a CT feature-based score including vessel infiltration, thrombus extension, and arterial hyperenhancement.
ResultsID measurements demonstrated excellent inter- and intra-rater agreement (ICC ≥ 0.99). ID was significantly higher in neoplastic PVT in both phases. Diagnostic performance was high, with sensitivities and specificities of 100% and 95.9% in LAP and 93.1% and 100% in PVP (AUC 0.98 (95% CI: 0.95–1.00) and 0.97 (95% CI: 0.92–1.00)). The feature-based score showed lower accuracy. In non-HCC malignancies, ID achieved high diagnostic accuracy in PVP.
ConclusionID derived from PCD-CT reliably differentiates neoplastic from bland PVT in HCC and outperforms conventional CT features. In non-HCC malignancies, ID is particularly accurate in the portal venous phase, supporting its broader clinical utility as an imaging biomarker in this contrast media phase.
Key Points