Usefulness of Cone-Beam CT-Based Liver Perfusion Mapping for Evaluating the Response of Hepatocellular Carcinoma to Conventional Transarterial Chemoembolization.

Sun Young Choi,Woosun Choi,Soo Buem Cho,Kyung Ah Kim,Yohan Kwon

doi:10.3390/jcm10040713

Abstract

We investigated the cone beam computed tomography (CBCT)-based-liver-perfusion-mapping usefulness during transarterial chemoembolization (TACE) in hepatocellular carcinoma (HCC) to access treatment response and predict outcomes. From October 2016 to September 2018, 42 patients with HCCs scheduled for conventional TACE were prospectively enrolled. Three reviewers evaluated the unenhanced and contrast-enhanced CBCT and CBCT-based-liver-perfusion-mapping of each tumor. Parenchymal blood volume (PBV) was measured. The operator’s judgment on the technical results was recorded. Response outcome was determined on follow-up CT or magnetic resonance imaging, according to the modified Response Evaluation Criteria in Solid Tumors. Diagnostic performance for detection of a viable tumor was evaluated using multiple logistic regression with C-statistics. CBCT-based-liver-perfusion-mapping and the maximum PBV of the tumor were significant in multiple logistic regression analysis of response (p < 0.0001, p = 0.0448, respectively), with C-statistics of 0.9540 and 0.7484, respectively. Diagnostic accuracy of operator’s judgment was 79.66% (95%CI 69.39%–89.93%). Diagnostic performance of CBCT-based-liver-perfusion-mapping showed a high concordance in three reviewers. The mean PBV of tumor, maximum PBV of tumor, and mean PBV of liver significantly decreased after TACE (each p < 0.001). In ROC curve analysis, the AUC for prediction of residual tumor by the maximum PBV of tumor after TACE was 0.7523, with 80.8% sensitivity and 60.6% specificity.

Highlights

Quantifying tumor angiogenesis is important for evaluating disease progression and monitoring response to therapy in hepatocellular carcinoma (HCC) [1,2]
Unenhanced cone beam computed tomography (CBCT) is limited in accurately evaluating viable tumor portion because it can only estimate the ethiodized oil deposition in the tumor
Immediate treatment response was evaluated based on three types of CBCT images (Figure 2)

Summary

Introduction

Quantifying tumor angiogenesis is important for evaluating disease progression and monitoring response to therapy in hepatocellular carcinoma (HCC) [1,2]. Conventional computed tomography (CT) perfusion imaging is a noninvasive, quantitative technique that assesses tissue perfusion by measuring the passage of a bolus of iodinated contrast medium through a vascular system and allows calculation of several physiological parameters, including parenchymal blood volume (PBV) [3,4,5]. This approach cannot provide intraprocedural measures of tissue perfusion. In dual-phase CBCT, any residual viable tumor may be missed due to the heterogeneity of ethiodized oil deposition throughout the tumor and the regional noncancerous hepatic parenchyma, in small tumors, because of the similar density of ethiodized oil and iodine contrast agent, which can lead to incomplete TACE, worsening the prognosis [14,15]

Methods

Results

Discussion

Conclusion