LA Times -- Avastin is a widely used cancer drug that has been shown to be effective against a variety of tumors, including kidney, bowel, ovarian and lung cancer, but the drug produces more than four times the normal risk of a kidney disease called proteinuria in those who use it, researchers reported Friday. Such problems have already been noted anecdotally, but the new study is the first to document the extent of the problem, showing that it affects more than 2% of those who use the drug. Most experts agree that the increased risk is not a sufficient reason to stop using Avastin, which can prolong life, but the findings reinforce the need for physicians to monitor kidney health in patients receiving it.