Circulating tumor cells criteria (CyCAR) versus standard RECIST criteria for treatment response assessment in metastatic colorectal cancer patients

• Published in: Journal of translational medicine Vol. 16; no. 1; p. 251
• Main Authors: Delgado-Ureña, Mayte, Ortega, Francisco G, de Miguel-Pérez, Diego, Rodriguez-Martínez, Alba, García-Puche, Jose L, Ilyine, Hugh, Lorente, Jose A, Exposito-Hernandez, Jose, Garrido-Navas, M Carmen, Delgado-Ramirez, Miguel, Serrano, M José
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 06.09.2018; BioMed Central; BMC
• Subjects: Antineoplastic Combined Chemotherapy Protocols - therapeutic use; Bevacizumab; Biomarkers; Breast cancer; Cancer research; Cancer therapies; Care and treatment; Cell Line, Tumor; Chemotherapy; Circulating tumor cells; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - drug therapy; Colorectal Neoplasms - pathology; Criteria; CyCAR; Female; Fluorouracil - therapeutic use; Follow-Up Studies; Genetic aspects; Humans; Immunomagnetic separation; Immunotherapy; Kinases; Leucovorin - therapeutic use; Male; Medical prognosis; Metastases; Metastasis; Metastatic colorectal cancer; Middle Aged; Monoclonal antibodies; Multivariate Analysis; Mutation; Neoplasm Metastasis; Neoplastic Cells, Circulating - pathology; Organoplatinum Compounds - therapeutic use; Patients; Prognosis; Proportional Hazards Models; Receptors, Vascular Endothelial Growth Factor - metabolism; RECIST; Reference Standards; Response Evaluation Criteria in Solid Tumors; Solid tumors; Targeted cancer therapy; Treatment Outcome; Tumor cells; Tumors; Vascular endothelial growth factor; Vascular endothelial growth factor receptors; Prognosis; RECIST; Circulating tumor cells; CyCAR; Metastatic colorectal cancer; Bevacizumab
• ISSN: 1479-5876; 1479-5876
• DOI: 10.1186/s12967-018-1624-2

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. 77 mCRC blood samples from FOLFOX-bevacizumab treated patients were analyzed to isolate CTCs before and after (12 and 24 weeks) treatment, using an immunomagnetic separation method. VEGFR expression was identified by double immunostaining. 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.