Bevacizumab, a novel antiangiogenic agent widely used to inhibit tumor growth, may significantly increase the risk of venous thromboembolism (VTE), a leading cause of complications and death in patients with cancer. Researchers performed a meta-analysis of 15 studies that compared standard antineoplastic therapy, with and without bevacizumab. The analysis included almost 8,000 patients with various advanced solid tumors.

Bevacizumab increased the incidence of VTE by 33%; both high-dose and low-dose bevacizumab were associated with significantly increased risk. The risk was greatest for patients with aerodigestive (lung, head and neck, and esophageal) cancer and mesothelioma. The risk was lower in patients with breast cancer and renal cell carcinoma. If VTE develops, the researchers write, "anticoagulation is indicated, and bevacizumab may be continued if the benefits of the drug outweigh the risk."

Source: Nalluri SR, Chu D, Keresztes R, Zhu X, Wu S. Risk of venous thromboembolism with the angiogenesis inhibitor bevacizumab in cancer patients: a meta-analysis. JAMA. 2008;300(19):2277-2285.