EASL and mRECIST responses are independent predictors of survival in hepatocellular carcinoma patients treated with cryoablation

Objective The aim of this study was to determine which response evaluation criteria will best help predict the treatment efficacy of cryoablation for hepatocellular carcinoma. Materials and methods We retrospectively analyzed clinical data of 64 patients with hepatocellular carcinoma treated with cryoablation. Triphasic helical computed tomography scans were analyzed on the basis of WHO, Response Evaluation Criteria In Solid Tumors 1.1 (RECIST 1.1), modified RECIST (mRECIST), and European Association for the Study of the Liver (EASL) guidelines. We assessed the concordance among response guidelines and selected the most reliable model depending upon the correlation with overall survival. Results Both objective response rates and disease control rates were higher for mRECIST and EASL than for WHO and RECIST 1.1 for both overall responses and target responses. The kappa-value of comparisons between WHO and RECIST 1.1 and mRECIST and EASL was not more than 0.20 for both overall responses and target responses. There was consistency between WHO and RECIST 1.1 [kappa = 0.82, 95% confidence interval (CI): 0.72-0.91 for overall responses and kappa = 0.87; 95% CI, 0.76-0.94 for target responses], the same as that between mRECIST and EASL (kappa = 0.91, 95% CI, 0.73-0.98 for overall responses and kappa = 0.88, 95% CI, 0.72-0.95 for target responses). There was no significant association with survival for WHO and RECIST 1.1 responses or all target responses. The Cox-regression model showed that both mRECIST and EASL were independent predictors of overall survival, with a 51% risk reduction for mRECIST and a 61% risk reduction for EASL. Conclusion The enhancement models including mRECIST and EASL guidelines should be used in preference to WHO, RECIST 1.1, or target responses to assess the efficacy of cryotherapy. Eur J Gastroenterol Hepatol 25:620-627 (C) 2013 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.