Treatment or observation following detection of prostate cancer by PSA screening?

This study used a simulation model to review the benefits and harms of either treating, or simply observing, patients diagnosed with prostate cancer by prostate specific antigen screening.

Prostate specific antigen (PSA) is a molecule produced by cells of the prostate gland, and is normally present at very low levels in the blood. Since levels of PSA increase in the presence of prostate cancer, a simple blood test measuring PSA levels is the standard screening method for prostate cancer. From the time regular PSA screening has been initiated, a sharp increase in the amount of people being diagnosed with prostate cancer has been noted. Since this new rate of diagnosis dramatically exceeded the known incidence of prostate cancer, this raised the question of whether or not every man diagnosed by PSA screening should receive immediate treatment. Prostate cancer can be slow to grow, and treatment of cancer involves many risks and side effects. Therefore, watchful waiting (meaning simply observing patients), and treating patients only when necessary (when a tumor develops) has been recommended in many cases.

This article reviewed the potential benefits and harms of immediate treatment verses observation in newly diagnosed prostate cancer patients by PSA screening. The authors of this article used a simulation model based on statistical data, rather than using clinical data from actual patients.

Results from this data simulation showed a largely varying benefit to immediate treatment. The average life years gained by immediate treatment ranged from 0.1 to 4.0. The percentage of men who avoided death from prostate cancer ranged from 1.5% to 32.1%. However, 2.7% to 60.1% of patients are likely to have been overdiagnosed (diagnosed with prostate cancer although a dangerous tumor has not developed yet). The most benefit from immediate treatment compared to the harm produced (side effects from treatment) was shown to be in the 55 to 59 age group.

Overall, the harm to benefit ratio was favorable towards immediate treatment for men aged 55 to 59. In other age groups the harm to benefit ratio indicated that immediate treatment might not be beneficial in all cases.

The study described in this article is based on theoretical models. The analysis did not take into consideration any treatments other than radical prostatectomy (surgical removal of the prostate), such as radiation therapy.

Consult with your physician on the best treatment plan suited for your condition.