CT-Based Intratumoral Artery-Like Volume for Pretreatment Lung Shunt Estimation in Hepatocellular Carcinoma.

PURPOSE: To determine the clinical utility of automated 3-dimensional (3D) computed tomography (CT)-based quantification of intratumoral artery-like volume (IAV) for the preprocedural assessment of transarterial radioembolization (TARE) eligibility by ruling out high lung shunt fraction (LSF) in patients with large hepatocellular carcinoma (HCC).

MATERIALS AND

METHODS

This single-center retrospective study included patients with a single-nodular HCC (≥5 cm) who underwent both multiphasic CT and LSF measurement (2009-2024). LSF values were derived from technetium-99m macroaggregated albumin (MAA) scintigraphy. Automated 3D segmentation on arterial-phase CT defined tumor and aorta; IAVs were quantified using 5 thresholds (65%-85% at 5% intervals) relative to mean aortic Hounsfield unit. IAV metrics were compared across LSF groups (≤10%, 10%-20%, and >20%). Receiver-operating characteristic (ROC) analysis evaluated performance for LSF of >10% and >20% and determined cutoffs at fixed 80% and 90% sensitivities.

RESULTS

Of 169 patients, 123, 26, and 20 had LSF of ≤10%, 10%-20%, and >20%. IAV metrics at all thresholds showed a significant stepwise increase across these groups (P < .001). For predicting LSF of >10% and >20%, the area under the ROCs of IAV metrics ranged from 0.732 to 0.741 and 0.790 to 0.806, respectively. Using IAV75% as a representative metric, fixed 80% and 90% sensitivities yielded specificities of 50.4% (62/123) and 39.0% (48/123) for LSF of >10% (cutoffs, 0.06 and 0.02 cm3) and 74.5% (111/149) and 57.7% (86/149) for LSF of >20% (cutoffs, 0.50 and 0.16 cm3), respectively.

CONCLUSIONS

Automated CT-based IAV enables objective LSF risk stratification in large HCC and can identify low-risk patients preprocedurally, supporting a more streamlined TARE workflow.