Maintenance Metronomic Chemotherapy for Metastatic Colorectal Carcinoma

Colorectal cancer patients with metastases (mCRC) at response under expensive chemotherapy which may be toxic +/- exhausting are candidates for an effective and more convenient maintenance treatment. Objectives: 1. To define the efficacy of maintenance chemotherapy by a low-dose metronomic (LDM) regimen, in metastatic CRC patients responding under FOLFIRI + bevacizumab. 2. To discover predictive factors for response to this LDM regimen. Hypothesis: 1. The re-growth of residual metastases can be slowed by the anti-angiogenic effects of LDM chemotherapy. 2. Serial measurements of angiogenic/ inflammatory factors in the plasma and/or evaluation of certain enzymes in the tumor may discover predictive factors of response to LDM chemotherapy in metastatic CRC patients.