COLOSPOT Study : Assessment by EPISPOT of Circulating Tumor Cells in Patients With Metastatic Colorectal Cancer
Treatment of metastatic colorectal cancer needs chemotherapy in most of the cases. During these last years, many new chemotherapies and targeted therapies have been developed improving significantly the overall survival of patients. However, the choice of the therapeutic sequences becomes difficult due to the lack of validated predictive biomarkers of their efficiency. Indeed, only the mutation of the k-ras oncogene is a predictive factor of non-efficacy of the anti-EGFR antibodies. It is thus crucial to identify new biomarkers to propose the best personalized 1rst line therapeutic sequence. One idea would be to enumerate and characterize the circulating tumor cells (CTC) which, as it has been described in a recent study realized by Cohen et al. in patients with metastatic colorectal cancer, would give us an early evaluation of the therapeutic efficiency. In this context, the investigators have developed an innovative technology, the EPISPOT assay (patent of the University Medical Center of Montpellier), that allows the detection & characterization of viable CTC in the peripheral blood. The EPISPOT technology has been already evaluated in the breast and prostate cancer. Thus, the investigators would like to perform a prospective study on a cohort of patients with metastatic colorectal cancer to confirm, with this technology, the predictive value of CTC count for the efficacy of the treatment.