Spectral Computed Tomographic Parameters Predict the Therapeutic Efficacy and Overall Survival of the Angiogenesis Inhibitor AL3818 in Hepatic Lesions: Preliminary Animal Study

Objective This study aimed to investigate the predictive and prognostic values of repeated spectral computed tomographic (CT) parameter changes for the prediction of treatment responses to the angiogenesis inhibitor AL3818 in hepatic tumors. Methods A total of 30 rabbits with VX2 hepatic tumors that underwent spectral contrast-enhanced abdominal CT before and during treatment were included in the study. The percent change (Δ, %) of the normalized iodine concentration (nIC) during the arterial phase (AP) and venous phase (VP) was used to predict the tumor response and to calculate the overall survival (OS). The threshold of the nIC for tumor response prediction and prognostic significance was determined by a receiver operating characteristic curve and Kaplan-Meier analysis. Results After treatment, there were 43% (13/30) responders and 57% (17/30) nonresponders. When ΔnICAP ≥ -13.10% was used as the threshold, the sensitivity and specificity for the prediction of tumor response were 82.41% and 92.31%, respectively. ΔnICVP resulted in 88.20% sensitivity and 76.92% specificity for cutoff values ≥10.78%. Kaplan-Meier analyses showed that high ΔnICAP and ΔnICVP were associated with improved OS. Conclusions The current study shows the capability of the changes (Δ) in repeated spectral CT parameters to predict the tumor response during antiangiogenesis therapy in small hepatic tumors. ΔnICAP and ΔnICVP were predictors for treatment response and were associated with OS.