 - Patients are eligible with diagnosis of measurable metastatic colorectal carcinoma and radiologic documentation of disease progression during or with 3 months after termination of standard chemotherapy fluoropyrimidine-based therapy with oxaliplatin and irinotecan. Patients who had to interrupt the 1st or 1nd line therapy due to intolerance or who were refractory or intolerant to the standard treatment regimens are eligible, too. Bevacizumab can, but does not need to be administered at discretion of treating physician. Patients with K-RAS wild-type can be treated with cetuximab or panitumumab before they enter the study. 