According to Stony Brook University researchers, the use of bevacizumab (Avastin) in combination with chemotherapy greatly increases the risk of gastrointestinal perforations in cancer patients, which are potentially life-threatening. The researchers found the overall incidence of GI perforation among 12,294 patients with a variety of solid tumors was 0.9% (the death rate was 21.7%), but patients who took bevacizumab were twice as likely to develop GI perforations.