Comparison of volume perfusion computed tomography and contrast-enhanced ultrasound for assessment of therapeutic effect of transarterial chemoembolization in patients with hepatocellular carcinoma: a preliminary report

Abstract

Background

Evaluation of transarterial chemoembolization (TACE) by using contrast-enhanced ultrasound (CEUS) and volume perfusion computed tomography (VPCT) as methods that display tumor vascularization.

Purpose

To assess early results of TACE in patients with hepatocellular carcinoma (HCC) using CEUS and VPCT.

Material and Methods

Twenty patients with HCC underwent CEUS and VPCT in the pre- and post-TACE setting (1 day). Hepatic perfusion index (HPI), arterial liver perfusion (ALP), blood flow (BF), and blood volume (BV) were measured with VPCT. Peak intensity (PI), time-to-peak (TTP), and regional blood flow (RBF) were measured with CEUS. Sensitivity, specificity, negative and positive predictive values, and cutoff values for these parameters were calculated. Immediate tumor response after TACE was classified as responder or non-responder. Results were compared with those at follow-up after 2 and 4 months (FU_2mo/FU_4mo) following modified RECIST.

Results

CEUS and VPCT showed comparable immediate post-TACE results in 20/20 cases. Complete response was confirmed in 10/20 patients at FU_2mo and in 9/20 at FU_4mo. For responders, reduction in HPI, ALP, BV, and BF at day 1 post TACE proved significant (P < 0.001). For non-responders, the course of all VPCT parameters proved non-significant. A cutoff of 40% reduction in HPI and a reduction in ALP of >29.6%, in BV of >41.4%, or in BF of >53.1% was indicative of response according to FU_2mo. For responders only, changes in PI (P < 0.001), TTP (P < 0.01), and BF (P < 0.01) proved significant whereas for non-responders, all CEUS parameters proved non-significant.

Conclusion

CEUS performs equally to VPCT for assessment of early response to TACE in HCC by a lesion-by-lesion assessment and showed prognostic value at mid-term.