AUTHOR=Zhou Meng , Zhang Chunhui , Nie Jianhua , Sun Yajuan , Xu Ye , Wu Fangfang , Huang Yuhong , Li Shun , Wang Yuan , Zhou Yang , Zheng Tongsen 

TITLE=Response Evaluation and Survival Prediction Following PD‐1 Inhibitor in Patients With Advanced Hepatocellular Carcinoma: Comparison of the RECIST 1.1, iRECIST, and mRECIST Criteria

JOURNAL=Frontiers in Oncology

VOLUME=Volume 11 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2021.764189

DOI=10.3389/fonc.2021.764189

ISSN=2234-943X

ABSTRACT=Background Precise evaluation of the efficacy of immunotherapy is critical in the effective management and treatment of advanced hepatocellular carcinoma (HCC). Therefore, the purpose of this study was to compare the response assessments achieved by different criteria and to evaluate the correlation between survival outcome and response assessment in HCC treated with PD-1 inhibitor.
Methods Fifty patients with advanced HCC treated with first-line PD-1 inhibitor with baseline and follow‐up CT images were analyzed. The patients were categorized into responders [complete response (CR) or partial response (PR)] and non‐responders [stable disease（SD）or progressive disease（PD)] according to the criteria. 
Results When the response assessments between RECIST 1.1 and mRECIST were compared, no statistically significant differences were observed. Overall response rate was 16% by RECIST 1.1 and iRECIST and was 22% by mRECIST. According to RECIST 1.1 and mRECIST, overall survival (OS) and progression-free survival (PFS) were not statistically different between the CR and PR groups and the SD and PD groups. The OS and PFS were significantly different between responders and non-responders according to mRECIST. The Cohen’s Kappa for RECIST 1.1, iRECIST and mRECIST was 0.534, 0.438, and 0.363, respectively.
Conclusion The mRECIST criteria have a powerful ability to discriminate between responders and non-responders and demonstrated significantly longer OS and PFS in responders than in non-responders. However, mRECIST needs to be further improved in order for it to be widely used in the clinical evaluation of immunotherapy in HCC.