Both a digital rectal examination and a prostate-specific antigen (PSA) blood level are recommended annually for men over 50. If a father, brother or uncle has had prostate cancer, these annual tests should be started at age 40. These tests may detect cancer of the prostate before it has spread.
The digital rectal examination is useful because the prostate gland's location within the rectum makes it easy to feel. The cancer often produces a lump or an irregularity that can be felt, and about one suspicious area in three will prove to be malignant .
PSA is often elevated when cancer is present. Since PSA will usually rise as tumors grow, measuring it is a good way to monitor the course of cancer once it is found. Its role in screening is less clear because it can also be elevated in benign disease or normal with cancer. Accordingly, efforts to adopt PSA as a routine screening test have led to controversy. On the one hand, since half the prostate cancers now detected have spread by the time they are discovered, it may be useful to find them earlier, before they have spread. On the other hand, while screening will probably detect many more prostate cancers earlier, research has not yet shown that such men will be less likely to die from their disease than unscreened men who are found to have prostate cancer during usual visits to their physician. Also, while screening may lead to treatment that may reduce prostate cancer death rates, it may also lead to unnecessary treatments in the thousands of men who might otherwise lead normal lives because they would not need treatment at all.
