Information about the PSA Test and its use in Prostate Cancer from the BC Cancer Agency

The PSA test is a blood test that measures a substance produced by the prostate, called prostate specific antigen (PSA). There are 3 potential uses for PSA:

1. PSA may be used for monitoring of established prostate cancer and metastatic disease (spread of prostate cancer) or detection of early recurrence of prostate cancer, where prostate cancer is already known.
2. PSA may be used as a diagnostic adjunct in combination with other tests for early detection of prostate cancer in symptomatic men with:
   • Urinary symptoms
   • Suspicious digital rectal examination findings
   The standard method of early detection for prostate cancer is the digital rectal examination (DRE) which should be done annually in fit men 50-70 years or if obstructive or other urinary tract symptoms are present.
3. Screening tool for all men
   • PSA testing is of unknown value as a population screening test. Although there is good evidence that it increases the detection rate of early stage, clinically significant prostate cancers, there is little evidence to date that such early detection leads to reduced mortality; the "gold standard" for evaluating screening tests.

Fit men, age 50-70 (men with at least 10 years life expectancy) should be made aware of the potential benefits and risks of early detection so that they can make an informed decision as to whether to have the test performed.

Additional Information about PSA:

• PSA levels of less than 4 ( may vary with age ) are considered normal, however a prostate cancer may exist even though levels are normal. The upper limit of normal depends on age and race.
• PSA levels over 4 may be considered elevated and may indicate benign disease or prostate cancer. The higher the level, the more likely the presence of cancer.
• If a PSA level is elevated, a referral to a urologist is indicated.
• If healthy men with no symptoms want a PSA test , they should speak to their family physician. The cost is approximately $35.00. The PSA test may be covered by the medical plan if a physician has reason to suspect the patient may have cancer and feels the test is necessary due to suspicious symptoms.

Many prostatic tumours can be felt with a rectal exam. However, small localized tumours are more likely to be detected by a combination of PSA and rectal exam.

To assist British Columbian men in making informed decisions about testing for prostate cancer, the BC Cancer Agency has created a pamphlet – "The Pros and Cons of PSA Screening for Prostate Cancer" - outlining the risks and benefits of testing.

The blood test commonly used to detect the presence of prostate cancer – the prostate specific antigen test (PSA) – is a controversial screening tool. Before requesting the test, the BC Cancer Agency believes that men should be informed of the pros and cons. The pamphlet, developed in collaboration with the Vancouver Prostate Support and Awareness Group, offers information about prostate cancer, other prostate conditions, reasons to test, and reasons not to test.

"The BC Cancer Agency has a responsibility to help men make informed decisions about PSA testing," explains Dr. Tom Pickles, chair of the BC Cancer Agency's prostate tumour group. "Our mandate covers the full spectrum from prevention to treatment, and screening is part of this mandate."

There are valid reasons for and against the decision to have a PSA test, explains Dr. Pickles. The usefulness of PSA as a detection tool for prostate cancer is a controversial subject – there is no clear agreement among health care experts that a PSA test offers a definitive answer about what a man should do.

See the full-text Patient Information Document.

Revised Sept. 2003
Genitourinary Tumour Group