The purpose of this study is to compare efficacy of bevacizumab monotherapy with standard chemotherapy (DTIC) in patients with metastatic malignant melanoma. In addition, we want to evaluate the predictive value of a set biomarkers associated with vascular endothelial growth factor (VEGF) dependent angiogenesis. Also, we aim to identify mechanisms causing acquired resistance to treatment with bevacizumab and escape mechanisms caused by other angiogenic growth factors than VEGF. Finally, we want to analyze safety and influence on outcome variables by primary prevention of bevacizumab induced hypertension by low dose beta blockers in comparison with an ACE inhibitor.