New prostate cancer drugs come to market quite rarely because the studies mandated by the FDA cost hundreds of millions of dollars. The FDA requires these studies to randomly allocate men into two comparison groups. One group receives the new medicine being tested. The other group gets an ineffective fake, called a placebo. Assuming the study is performed in an acceptable manner, the FDA will approve a new drug for commercial use, only if the men who are receiving the new medicine outlive those treated with the placebo by a specified margin without excessive toxicity.

Studies designed to evaluate the effectiveness of surgery for prostate cancer take a long time to perform because prostate cancer grows much slower than other cancers.  Since it is primarily in older men, mortality from unrelated causes—other cancers, heart disease and simply old age—frequently occurs before the prostate cancer progresses enough to impair health.