Dramatic increases in survival combined with an increase in rates of diagnosed prostate cancer seems to be a very convincing argument that PSA testing has been very beneficial for men.
There are other factors at work. While early treatment for prostate cancer seems to be helpful, we need to understand that as cancer is now diagnosed much earlier than it had been a few decades ago, men will naturally live longer with their disease regardless as to what type of, if any, treatment were given. A number of studies have attempted to answer the PSA screening question but were poorly designed and executed and the validity of the results have been hotly debated. Teasing out how much of that downward swing is from statistical anomalies and how much is from saved lives has been a topic of much debate... and will not likely be definitively answered any time soon.
What is the bottom line? The AUA (American Urological Association) to which I belong believes that prostate cancer screening - with PSA testing - should be done annually beginning at age 40. I support that recommendation. More importantly, I support the right of each individual to have the ability to decide for himself whether or not he would like to be screened for prostate cancer and not have the decision made for him by a small government committee.