Immediate post-doxorubicin drug-eluting beads chemoembolization Mr Apparent diffusion coefficient quantification predicts response in unresectable hepatocellular carcinoma: A pilot study

Purpose To investigate magnetic resonance imaging (MRI) diffusion-weighted imaging (DWI) of hepatocellular carcinoma (HCC) immediately post-doxorubicin drug-eluting beads transcatheter arterial chemoembolization (DEB-TACE) therapy as an early imaging biomarker of therapy response. Materials and Methods In a single-center prospective correlative study, 12 consecutive patients, median age 64 years, underwent DEB-TACE and dynamic contrast-enhanced (DCE) and DWI (b = 50,400,800 s/mm²) MRI at baseline with respect to first DEB-TACE, within 3 hours, and at 1 and 3 months posttherapy. DCE imaging response was evaluated according to target mRECIST and EASL. Relative change (RC) in apparent diffusion coefficient (ADC) of treated lesions was measured on follow-ups. Correlation between ADC RC in tumors and anatomical response were evaluated with paired t-test and receiver operator characteristic (ROC) curve. Survival from first DEB-TACE was estimated using Kaplan-Meier and log-rank analysis. Results Compared to baseline, mean ADC increased significantly for responders within 3 hours post-DEB-TACE (0.73 ± 0.20 mm²/s vs. 0.99 ± 0.28 mm²/s × 10^-3 (P = 0.001)). There was no significant change in ADC within 3 hours for nonresponders. ADC RC threshold of 20% immediately post-DEB-TACE showed 100% sensitivity and specificity in predicting anatomical response at 1 and 3 months with patients with ≥20% ADC increase demonstrated significantly prolonged mean overall survival compared to others (25.4 vs. 13.3 months (P = 0.017)). Conclusion ADC relative change of ≥20% immediately post-DEB-TACE is an accurate predictor of objective and quantitative treatment response and prolonged survival in unresectable HCC. J. Magn. Reson. Imaging 2015;42:981-989.