Sequential first-line therapy in metastatic colorectal cancer with Capecitabine/FUFA, Irinotecan and Bevacizumab

Primary objectives: Evaluation of effectiveness in correlation to tolerability of both therapy schemes in patients with metastatic colorectal cancer without Prior therapy. Primary endpoints: - Time to failure of treatment strategy (TFS) - If a comparable TFS is reached in both treatment arms, an analysis of the adverse effects should help to define the superior treatment strategy. Treatment related toxicity will be evaluated by analysis of all grade 2-5 toxicities divided by the number of administered treatment cycles within the TFS time intervall