Comparison of WHO and RECIST criteria for response in metastatic colorectal carcinoma

Purpose: This study compared the WHO criteria with the response evaluation criteria in solid tumors (RECIST) in the same patients with metastatic colorectal cancer in order to determine the significance of the RECIST. In addition, this study compared the estimations of medical oncologists with those of a radiologist.

Materials and methods: Between 2002 and 2005, a total of 48 patients (male: female ratio, 29:19; median age, 58 years) with measurable lesions receiving chemotherapy for metastatic colorectal carcinoma were enrolled in this study. Two medical oncologists and one radiologist, who were blinded to the patients' condition, independently reviewed all the CT images. The results were compared using a kappa test.

Results: The kappa test for concordance between the WHO and RECIST criteria of the medical oncologists and the radiologist were 0.908 and 0.841, respectively. The level of concordance between the investigators using the WHO and RECIST were 0.722 and 0.753, respectively.

Conclusion: The RECIST criteria are comparable to the WHO criteria in evaluating the response of colorectal carcinoma, but have simple and reproducible guidelines. The use of RECIST is recommended for evaluating the treatment efficacy in clinical trials and practice.