Circulating tumor cells criteria (CyCAR) versus standard RECIST criteria for treatment response assessment in metastatic colorectal cancer patients Delgado Ureña, Mayte Ortega, Francisco G. Miguel-Pérez, Diego de Rodríguez Martínez, Alba García Puche, José Luis Ilyine, Hugh Lorente Acosta, José Antonio Expósito Hernández, José Garrido Navas, María del Carmen Delgado Ramírez, Miguel Serrano, M. Jose Metastatic colorectal cancer Bevacizumab Circulating tumor cells RECIST CyCAR Prognosis The use of circulating tumor cells (CTCs) as indicators of treatment response in metastatic colorectal cancer (mCRC) needs to be clarified. The objective of this study is to compare the Response Evaluation Criteria in Solid Tumors (RECIST) with the Cytologic Criteria Assessing Response (CyCAR), based on the presence and phenotypic characterization of CTCs, as indicators of FOLFOX–bevacizumab treatment response. We observed a decrease of CTCs (42.8 vs. 18.2%) and VEGFR positivity (69.7% vs. 41.7%) after treatment. According to RECIST, 6.45% of the patients did not show any clinical benefit, whereas 93.55% patients showed a favorable response at 12 weeks. According to CyCAR, 29% had a non-favorable response and 71% patients did not. No significant differences were found between the response assessment by RECIST and CyCAR at 12 or 24 weeks. However, in the multivariate analysis, RECIST at 12 weeks and CyCAR at 24 weeks were independent prognostic factors for OS (HR: 0.1, 95% CI 0.02–0.58 and HR: 0.35, 95% CI 0.12–0.99 respectively). CyCAR results were comparable to RECIST in evaluating the response in mCRC and can be used as an alternative when the limitation of RECIST requires additional response analysis techniques. 2019-11-14T11:25:56Z 2019-11-14T11:25:56Z 2018 info:eu-repo/semantics/article Delgado-Ureña, M., Ortega, F. G., de Miguel-Pérez, D., Rodriguez-Martínez, A., García-Puche, J. L., Ilyine, H., ... & Serrano, M. J. (2018). Circulating tumor cells criteria (CyCAR) versus standard RECIST criteria for treatment response assessment in metastatic colorectal cancer patients. Journal of translational medicine, 16(1), 251. http://hdl.handle.net/10481/57895 10.1186/s12967-018-1624-2 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España Springer Nature