To determine if a man is at risk for prostate cancer, doctors use a simple blood test called a Prostate Specific Antigen (PSA) test. This can be performed right in a physician’s office. For most men, annual PSA testing combined with a digital rectal exam (DRE) should begin at age 50. However, African-American men and men with a family history of prostate cancer should begin getting tested at age 40.
PSA is an enzyme that is produced only by prostate cells, either normal or cancerous, and secreted into the seminal fluid to keep it liquefied. A small amount of PSA is leaked into the bloodstream by prostate cells, which allows it to be measured. When a prostate cell is cancerous, it leaks more PSA into the bloodstream. On average, one cancerous prostate cell will produce 10 times more PSA than a healthy cell. When cancerous cells multiply, this causes a man’s PSA level to rise.
PSA is measured through nanograms per milliliter of blood (ng/ml). Abnormal PSA levels are defined as:
The higher the PSA normally means that more cancer is present. But there are some prostate cancers that do not produce a high level of PSA and can fool doctors. The best way to determine the amount of cancer in a patient is with a biopsy.
A prostate biopsy is performed by a urologist, who uses tiny needles to remove the suspected cancerous cells from the prostate. This is where the expertise of the urologist can make a difference. The urologist must get a tissue sample from many different areas of the prostate to fully evaluate the cancer.