For patients who have been previously treated with bevacizumab, any severe toxicity associated with bevacizumab while the patient was being treated with the agent will make the patient ineligible for the trial. This includes bevacizumab-induced hypertensive crisis, arterial thromboembolic events (including cardiac ischemia or cerebrovascular ischemia or other arterial thrombosis), nephrotic syndrome, gastrointestinal perforation, serious hemorrhage, and fistulas (unless the fistula completely resolved while the patient was still on bevacizumab or it has been surgically corrected).