First-line Therapy of Stage IV Colorectal Cancer

Inclusion Criteria: * Histologically proven inoperable colorectal cancer * Adult patients \>= 18 years of age * ECOG \<2 Exclusion Criteria: * Preceding chemo- or immunotherapy with the exception of adjuvant or neoadjuvant treatment of non-metastatic disease ending ≥ 6 month prior to study inclusion. Progression within 6 month after the end of adjuvant therapy must be excluded. * Other malignancies with the exception of basal cell carcinoma or successfully treated carcinoma in situ of the cervix uteri. * No history of severe comorbidities, i. e. uncontrolled hypertension, GI-bleeding, congestive heart-failure NYHA class II-IV, symptomatic coronary heart disease, myocardial infarction within 1 year prior to study inclusion, serious cardiac arrhythmias requiring medication, Grade II or greater peripheral vascular disease and other severe uncontrolled co-morbidities * No history of stroke or other CNS-diseases (tumors, seizure, transient ischemic attack etc.) * ≥ Grade II peripheral artery vascular occlusive disease * Preexisting neuropathy ≥ Grade 1 * Interstitial pneumonia or lung fibrosis * Serious, nonhealing wound, ulcer, or bone fracture * Preceding irradiation an indicator lesion except for documented progressive disease during irradiation and termination of irradiation ≥ 4 weeks from study inclusion * Thromboembolic or bleeding events within the last 6 month * Need for therapeutic anticoagulation (heparin, cumarin) * Use of ASS \> 325 mg/die or NSAR * Proteinuria \> 1+ (stix) as long as urine protein \>1g/24h