Prostate cancer screening doesn't cut death rates

A 20-years study from Sweden suggests that screening for prostate cancer does not substantially reduce the risk of death from the disease. On the other hand, a good many men might receive false-positive results and over-treatment, adding an element of risk to the widespread screening.

Last year the American Cancer Society revised its guidelines for screening prostate cancer, and reinforced the message that men need to be informed of the known benefits as well as limitations of screening. The American Cancer Society does not encourage nor discourage prostate cancer screenings.

Researchers looked at all men in the Swedish city of Norrkoping who were between the ages of 50 and 69 years in 1987 - a total of 9,026 men. Of these, 1,494 men were screened for prostate cancer - first with a digital rectal examination (clinical assessment using a finger) and, starting in 1993, with both clinical assessment and a blood test (for prostate specific antigen – PSA) - every three years. In 1996, only men aged 69 years or under were screened. The remaining 7,532 men did not undergo screening and served as a comparison group. The mortality rate for men who underwent screening was not significantly different from that in the control group, although tumours in the screened group tended to be in early stages (smaller and more localised).

In the light of the above findings, the benefit from screening is not sufficient to support mass screening. The study does carry with it several significant weaknesses. In particular, because of the timing and design of the study, most men really only received one and, at most, two PSA tests.

With more and more studies on the subject, guidelines have become vague recommendations, without any good rules anymore. Patients should therefore discuss the issue PSA testing with their doctors.