A committee within the F.D.A. has advised the agency to denounce its marketing approval of the popular cancer drug Avastin for treating breast cancer because “new trials showed no apparent benefit from the drug.” The committee found that new trials of the drug, which is combined with the breast cancer drug paclitaxel to treat metastatic breast cancer, actually showed that survival rates decreased slightly for women due to complications from the drugs. If the F.D.A. decides to follow the committee recommendation, it would not affect marketing of the drug for brain, lung, colon and kidney cancer.