Comparison of the RECIST 1.0 and RECIST 1.1 in patients treated with targeted agents: a pooled analysis and review

Patients treated with targeted agents were not included in the data warehouse when the RECIST 1.1 was revised in 2009. We conducted this pooled analysis to investigate the impact of the RECIST 1.1 on the assessment of tumor response in cancer patients treated with targeted agents. We surveyed MEDLINE, EMBASE and PubMed for articles with terms of the RECIST 1.0 or RECIST 1.1. We searched for all the references of relevant articles and reviews using the 'related articles' feature in the PubMed. There were six articles in the literature comparing the clinical impacts of the RECIST 1.0 and RECIST 1.1 in patients treated with targeted agents for advanced or metastatic cancer. A total of 322 patients were recruited from the six trials; 217 with non-small cell lung cancer, 23 with thyroid cancer, 20 with gastrointestinal stromal tumor, and 62 with renal cell carcinoma. Because of new lymph node criteria, eight patients (2.5%) had no target lesions when adopting the RECIST 1.1. The number of target lesions by the RECIST 1.1 was significantly lower than that by the RECIST 1.0 (P < 0.001). However, the RECIST 1.1 showed high concordance with the RECIST 1.0 in the assessment of best tumor responses (k = 0.908). Seventeen patients (5.6%) showed discrepancy in the best tumor response between the RECIST 1.0 and RECIST 1.1. This pooled study demonstrates that the RECIST 1.1 shows the highly concordant response assessment with the RECIST 1.0 in patients treated with targeted agents.