What is prostate specific antigen (PSA)?
Prostate Specific Antigen (or PSA) is an enzyme exclusively produced by the epithelial cells of the prostate gland. It is released in very small amounts into the bloodstream. When there is a problem with the prostate (like cancer, enlargement or infection) more and more PSA is released. It eventually reaches a level where it can be easily detected in the blood.
What is the function of PSA?
The function of PSA is for the ejaculate to liquefy semen to allow sperm to swim freely. It is also believed to create the correct pH balance for sperm to survive and also instrumental in dissolving cervical mucus, allowing easy entry of sperm into the uterus.
When do you do a PSA screening on your blood?
PSA screening does not lower your risk of having prostate cancer; it merely increases the chance that you will find out that you have it, before it is too late to treat. PSA testing can detect early-stage cancers that a digital rectal examination (DRE) would miss. PSA is done from the age of 50 in conjunction with a digital rectal exam (DRE) for prostate cancer screening. PSA is done from the age of 40 or 45 if you have a strong family history of prostate cancer and from the age of 45 in black men, who have a higher risk to develop prostate cancer.
What does an elevated PSA result mean?
Elevated levels of PSA in blood are associated with prostate cancer, but it is not a perfect test for cancer. The PSA level also tends to rise in men with benign prostatic hyperplasia or BPH (enlargement of the prostate) and is a good marker for prostate volume. PSA levels are usually also elevated in men with acute bacterial prostatitis (inflammation of the prostate). Recent ejaculation can also increase levels, as well as prolonged bike riding.
Pitfalls of a PSA:
Pitfalls of a PSA test is that a “normal” PSA level of 4 ng/ml or below does not guarantee that one is cancer-free; in about 15% of men with a PSA below 4 ng/ml, a biopsy will reveal prostate cancer. Another pitfall of a PSA is that some men with prostate cancer may even have low levels of PSA. PSA can also be diluted in men who are overweight or obese, due to a larger blood volume.
What other tests can be done with a PSA?
The PSA blood test and the digital rectal exam (DRE) are done in conjunction for prostate cancer screening. During a DRE, the medical doctor inserts a gloved, lubricated finger into the rectum and examines the prostate for any irregularities in size, shape, and texture.
Watch this video: – it conveys both the seriousness and the slightly ridiculousness of the procedure. At My Sexual Health we also know that everybody finds it a bit weird and uncomfortable, but we do it, because it is in your best interest to detect cancer early!
In conclusion, prostate cancer is a treatable condition these days, if it is detected early enough. Please ask your doctor to do a PSA level on you annually and don’t shy away from those rectal exams – it could save your life!
All of the MSH doctors offer prostate cancer screening, but you can have it done by any doctor. You do not need to see a urologist for a prostate check, unless your primary care doctor has picked up something suspicious or you have concerns that cannot be resolved by your GP.
Written by Dr Larisse Badenhorst