Inter- and intra-criteria reproducibility of RECIST ver 1.1 and modified EASL (European Association for the Study of the Liver) tumor response criteria to transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC): From the dataset of JIVROSG (Japan Interventional Radiology in Oncology Study Group) 0401

Abstract

e15501 Background: In spite of systemic response evaluation criteria, RECIST is widely used for evaluating the tumor response (TR) in local therapy. As a result, there are double standard criteria (RECIST ver 1.1 and modified EASL) in the evaluation for TR of HCC treated by TACE. Tumor size is evaluated by measurement of the entire lesion including necrotic part in RECIST ver 1.1 (EJC 2009;45:228), whereas the only contrast-enhanced part on radiological images is measured when the modified EASL are used (JNCI 2008;100:698). Both criteria adopt the unidimensional measurement. Methods: This is a study of the radiological findings of patients who underwent TACE for multiple HCCs in the JIVORSG 0401 study. The subjects were 65 lesions in 21 patients treated by pan- hepatic TACE using cisplatin and gelatin particles without mixing iodized-oil. Five radiologists measured independently each lesion twice, therefore 130 measurements were performed per radiologist according to the 2 criteria (RECIST ver 1.1 and modified EASL). To compare the inter- and intra- criteria reproducibility of TR for each lesion, CR rate, response rate, proportion of agreement, and the kappa statistics for response categories were calculated. Results: Results are shown in the table. CR rate and response rate obtained using the modified EASL were higher than those obtained using RECIST ver 1.1. The inter-criteria reproducibility between RECIST ver 1.1 and modified EASL were poor. The intra-criteria reproducibility of RECIST ver 1.1 indicated substantial agreement, while that of modified EASL indicated almost perfect agreement. Conclusions: For a precise interpretation of the tumor response in clinical trials of TACE for HCCs, appropriate attention must be paid to the criteria employed for the evaluation. [Table: see text] No significant financial relationships to disclose.