Prostate cancer is the most common cancer and the second leading cause of cancer death among men, with approximately 200,000 new cases detected and 30,000 deaths per year in the United States alone. These are surprising numbers, given the advances in prostate cancer diagnosis and treatment in recent years. However, in 2012 the United States Preventive Task Force published a strong recommendation against the routine use of prostate-specific antigen test. I’ll explain why this recommendation is a disservice to many men who could benefit from prostate screening and treatment.

What is the prostate-specific antigen test?

The prostate-specific antigen or PSA is a blood test used to determine men at risk for prostate cancer screening. It is the leading method of screening for prostate cancer. The screening can help catch the disease early when treatment may be more effective and have fewer side effects. It measures the level of prostate-specific antigen, a protein made by cells in the prostate gland (both normal cells and cancer cells). Prostate-specific antigen is mainly found in semen, but a small amount is also found in the blood. Blood levels can be elevated in people with prostate cancer.

During a prostate-specific antigen test, a small amount of blood is drawn from the arm and measured. The chance of having prostate cancer increases as the prostate-specific antigen level increases, but there is no set cutoff point that can tell if a man does or doesn’t have prostate cancer.

Prostate Cancer Testing

Many doctors use a prostate-specific antigen cutoff point of four ng/mL or higher when deciding if further testing is needed, while others might recommend it starting at a lower level. However, we advocate for more intelligent and responsible interpretations of the test, applying the knowledge that the prostate-specific antigen test will vary according to age, prostate size and ethnicity. With appropriate screening, we know we can decrease prostate cancer mortality by up to 20%.

• Most men without prostate cancer have prostate-specific antigen levels under four ng/mL of blood. When prostate cancer develops, the prostate-specific antigen level often goes above four. Still, a level below four does not guarantee that a man doesn’t have cancer. About 15% of men with a prostate-specific antigen below four will have prostate cancer if a biopsy is done.
• Men with a prostate-specific antigen level between four and 10 (often called the “borderline range”) have about a 1 in 4 chance of having prostate cancer.
• If the prostate-specific antigen is more than 10, the chance of having prostate cancer is over 50%.

If your prostate-specific antigen level is high, you might need further tests to look for prostate cancer.

Prostate Cancer Treatment

One reason for the criticism of prostate-specific antigen screening is the aggressive treatment of all prostate cancer patients. Yet, decades of research and observation have shown us that not all prostate cancers are created equally. Some prostate cancers are minor and, with proper surveillance, may never affect a patient’s health. In contrast, other prostate cancers are more aggressive and are better off being treated. The difficulty in the past has been determining which prostate cancers are the “bad” ones and deserve more aggressive treatment.

In general, low-risk prostate cancers are watched more under active surveillance, which means the cancer is not treated but monitored to ensure it doesn’t progress. Active surveillance frequently measures prostate-specific antigen levels and periodic prostate biopsies. If low-risk prostate cancers progress, or if a patient has a more aggressive form of the disease at the time of diagnosis, we can still achieve excellent outcomes with minimally invasive treatments.

Options for prostate cancers confined to the prostate gland include surgery or radiation therapy. Sometimes radiation is given following surgery. After surgery or radiation, hormone therapy is often given to decrease the risk of prostate cancer recurrence. Male sex hormones, specifically testosterone, are a driving factor for the development and progression of prostate cancer. Hormone therapy decreases the effect of testosterone on the cancer by reducing the production of testosterone or blocking the binding of testosterone to receptors on the cancer.