Physicians who have watched the data on prostate cancer screening for awhile could have seen this coming. When I counsel men on PSA (the antigen that screens for prostate cancer) screening, I tell them that the test more likely to harm them then help them. Most prostate cancers are slow growing and never cause problems. How can this be? Cancer is a growth of abnormal cells in your body. The body is always fighting off abnormal growths. It often suppresses early cancers through the immune system and other mechanisms. Even if a cancer continues to grow, it may take years and years to cause something bad. Most people die of a heart attack before the prostate cancer does anything bad.
Now there are a very small amount of people where prostate cancer kills people. The problem is that medicine does not have a way to detect these people. So as in breast cancer, universal screening of women under 40 will result in a lot of people getting mastectomies to prevent one "bad" cancer in women. In prostate cancer, if we screen everyone, we will make millions of men unable to get an erection or be able to hold on to their urine while trying to prevent one prostate cancer.
Screening is not the best way to stop cancer deaths. The best way to prevent them is to stop them in the first place. According to the World Cancer Research Report, you can prevent prostate cancer by eating a lot of fruits, vegetables, and whole grains; and by avoiding a high calcium diet. And that doesn't involve becoming impotent or incontinent.