Comparison of the RECIST and EORTC PET criteria in the tumor response assessment: a pooled analysis and review.

PURPOSE: The EORTC PET criteria (EORTC criteria) are used to assess metabolic tumor response in patients with solid tumors. We conducted this pooled study to compare tumor responses according to the RECIST and EORTC criteria.

METHODS: Electronic databases were searched for eligible articles with the terms of "RECIST" or "EORTC criteria". We found seven articles with the data on the comparison of tumor responses by the RECIST and EORTC criteria.

RESULTS: A total of 181 patients were recruited from the seven studies. Ninety-two patients (50.8%) received cytotoxic chemotherapy and 89 were treated with targeted agents. The agreement of tumor responses between the RECIST and EORTC criteria was moderate (k = 0.493). Of 181 patients, 66 (36.5%) showed disagreement in the tumor responses: tumor response was upgraded in 54 patients and downgraded in 12 when adopting the EORTC criteria. The estimated overall response rates were significantly different between the two criteria (52.5% by the EORTC vs. 29.8% by the RECIST, P < 0.0001). When comparing the two criteria according to the anti-cancer treatments (chemotherapy or targeted therapy), the levels of agreement in tumor responses were not excellent (k = 0.461 for chemotherapy and k = 0.524 for targeted therapy, respectively) regardless of therapeutic types.

CONCLUSION: This pooled study indicates that the concordance of tumor responses between the RECIST and EORTC criteria is not excellent. When adopting the EORTC criteria instead of the RECIST, the overall response rate was significantly increased.