An analysis of 21 studies has found that radiation treatment for prostate cancer may place men at a slight increased risk for other cancers such as bladder, colon, and rectal cancers. Oncologist Dr. Anthony Zietman writes, “[The study] confirms our belief that second malignancy should be added to the already long list of avoidable hazards associated with treatment for those men with low-risk prostate cancer who simply need no treatment at all.” He adds that concerns about secondary cancers “should not, however, stand in the way of an effective and well-studied treatment being given to men with higher grade, lethal prostate cancer for whom the potential benefit simply dwarfs the risk.”
British Medical Journal, March 2016