New guidelines from the influential U.S. Preventive Services Task Force take a conservative stance toward PSA prostate cancer screening. For men ages 55-69, the task force recommends that the decision to screen be left to individual patients. For patients ages 70 and older, the task force advised against screening entirely, noting that the relatively small potential benefit of preventing cancer did not outweigh more likely harms including false positives and the heavy physical toll of treatment.