Prognostic role of objective response in patients affected by hepatocellular carcinoma after loco-regional treatment: comparison between EASL and mRECIST criteria

Background: The European Association for the Study of the Liver (EASL) criteria and the modified Response Evaluation Criteria in Solid Tumors (mRECIST) are currently utilized to evaluate radiological response in patients affected by HCC and treated with loco-regional procedures. Several studies analysed the usefulness of these methods in predicting survival but there are not definitive data. Aim: To perform a systematic review of studies evaluating mRECIST and EASL criteria validity in predictive radiological response in HCC undergoing loco-regional therapies and their validity in predicting survival. Methods: A comprehensive search of the literature was performed in electronic databases EMBASE, MEDLINE, COCHRANE LIBRARY, ASCO conferences and EASL conferences from March 2000 to June 10, 2014. Our search strategy included terms for HCC, mRECIST, and EASL, loco-regional procedures included transarterial embolization (TAE), transarterial chemoembolization (TACE) and cryoablation. Inter-method agreement between EASL and mRECIST was evaluated using the k coefficient. For each criteria, overall survival was calculated in responders vs. non-responders patients, considering all target lesions response. Results: Among 18 initially selected publications, 7 reports were considered eligible. All studies were published as full-text articles. 1357 patients were included. Kappa coefficient, available or calculated, showed an high concordance (that is k value >0.8) in the evaluation of response between EASL and mRECIST criteria. The two methods were in agreement in defining the kind of response in 1286 patients, that is 94.77% (kappa index 0.928, 95%, CI 0.912-0.944). Proportion of responders according to mRECIST and EASL criteria was 62.4% and 61.3%, respectively. HR for overall survival (responders versus non responders) according to EASL and mRECIST was 0.39 (95% confidence interval 0.26 – 0.61, p <0.0001) and 0.38 (95% confidence interval 0.24 – 0.61, p <0.0001), respectively. Conclusion: In this literature-based meta-analysis, mRECIST and EASL criteria showed high concordance in HCC patients treated with loco-regional treatments. Objective response according to both methods confirmed a strong prognostic relation in terms of overall survival. This prognostic value appears to be very similar between the two criteria.