Prostate Specific Antigen (PSA)
Prostate Specific Antigen(PSA) is a glycoprotein produced by the prostate gland. Every anatomically normal man has a prostate gland. The prostate gland surrounds the neck of the urinary bladder. The gland produces a liquid juice which mixes with the semen during ejaculation. Semen itself is a creamy secretion that comes out when a man ejaculates, and it is made up of several components which come from the testis, the epididymis, seminal vesicles, prostate gland, Cowper’s gland, and the peri-urethral glands of Littre. Sperm cells are only a component of semen. They are not the only component. Some of these components help the sperm cells to survive. Others aid lubrication during coitus. PSA is one of those components. Its physiological function is to aid the liquefaction of semen. When semen comes out initially, it is thick creamy. After a few minutes, it liquefies and becomes as clear as water. Without liquefaction, the sperm cells cannot swim from the vagina of the woman into the Fallopian tubes where fertilization takes place. Some men who are infertile actually produce enough sperm cells, but abnormal liquefaction is the only problem they have. Therefore, the PSA is a vital chemical for reproduction.
Normally, only a small portion of PSA filters into the blood circulation. This is the part that is measured when tests are done for PSA. From the foregoing, it is easy to understand that PSA itself in the blood is not a disease, and that normal, healthy men do produce PSA. Therefore, there is no point in attempting to lower the level of PSA for its own sake. Most of it comes out along with semen during ejaculation. But under certain circumstances, a lot more spills into the circulation. It is important to understand that this would cause elevated levels of PSA in the circulation, but that does not necessarily mean prostate cancer. However, the most worrisome reason why PSA in the circulation should be above normal is prostate cancer.
In Kelina Hospital, we routinely measure 2 types of PSA: Free PSA and Total PSA. In people with prostate cancer, the cellular membranes and epithelial lining of blood vessels are destroyed by the cancer. This allows a lot of protein from the prostate gland and also a lot of PSA to leak into the circulation. However, a lot of the PSA is complexed with the proteins that equally leak out. Therefore, a lot more PSA is combined than free, in people with prostate cancer. Thus measuring Free PSA compared to Total PSA (which includes the PSA combined to proteins) will give us idea of whether we are dealing with prostate cancer or not. This will help avoid unnecessary biopsies (sampling of the prostate gland with a needle to see if there is cancer in it).
The common things that cause elevation in PSA are as follows:
1. Size of the Prostate
Normal, healthy prostate produces more PSA than prostate cancer does. A gland that is enlarged can produce a lot more PSA than smaller glands. The bigger the gland, the more the PSA it produces that spills into the blood stream. If PSA is found to be above normal, the next thing to look at is the size of the gland. The measurement that compares PSA value to size of the prostate is called PSA Density. PSA of 10 in a gland that is, say, 200g, is less frightening than PSA of 3 in a gland that is 30g. Usually, the laboratories would report that PSA values of 1-4ng/ml are normal. These references do not factor in the size of the prostate. Nothing can be farther from the truth than to say PSA of 0-4ng/ml is normal. It all depends on the size of the prostate. That is why PSA values should not be taken on face value. It takes a Urologist to interpret the value. Reference values of 0-4ng/ml are completely useless to an average Urologist.
2. Prostate Cancer
The most worrisome significance of raised PSA is Prostate Cancer. Generally, the higher the PSA, the higher the chance that somebody has prostate cancer. Some cancers do not produce a lot of PSA. Those cancers may be regarded as atypical or anaplastic. Anaplastic cancers are very aggressive. The cells are completely different from normal cells. The more the cancer cells resemble normal cells of that tissue, the less anaplastic they are. The more they resemble normal tissue, the more they behave like normal tissue. Therefore, anaplastic prostate cancers have the least tendency to behave like normal prostate. Sometimes they also do not produce a lot of PSA since PSA is produced by normal prostate cells much more than by cancer cells. In prostate cancer, a lot more of the PSA is combined with proteins, so the ratio of free to total PSA is very low.
3. Infection in the Urine
Patients with urinary tract infection tend to have higher PSA levels than at the time they did not have infection. Most times the levels fall lower after appropriate treatment of the infection. Note that it is wrong to take antibiotics without proper testing of the urine and recommendation by a certified medical personnel. Antibiotics cause a lot of harm to the body’s ability to fight infection on its own. Also, they stimulate bacteria to produce chemicals that can neutralize antibiotics or help the bacteria resist the medications. People who abuse antibiotics tend to develop infections caused by bacteria that turn out to be resistant to most commonly available antibiotics. Simply put, antibiotics breed superbugs!
4. Infection in the Prostate
Infection in the prostate is either acute or chronic. Acute prostatitis makes the person very sick, with fever, and a lot of prostration. PSA levels are very high in the blood. Recently, here in Kelina Hospital, we saw a man with PSA of 72ng/ml. It was all because of acute prostatitis. There is a lot of pain around the anus, because the prostate is located just in front of the anus. He could not pass urine. Fever was high grade. After treatment, PSA returned to 2ng/ml within one month. He did not need a biopsy.
5. Surgical Procedures involving the Prostate.
When patients have any form of surgical procedure on the prostate that does not involve removing the entire prostate gland, PSA levels in the blood rise sharply. This is often seen after a prostate biopsy.
PSA rises with age. The rate of rise with age is referred to as PSA velocity. The higher the velocity, the higher the chance there is cancer. But it does rise gradually with age even in those who do not have cancer.
After ejaculation, PSA levels the next day tend to be higher. Therefore, it is advisable to abstain from sexual activity at least 24 hours before PSA measurements.
8. Wrong Measurement
There are several machines that measure PSA. Some are not as accurate as others. Here in Kelina, we use a very advanced machine that cost us 20 times higher than previous machines we were using. We switched to this one because of accuracy. Kelina Hospital conducts PSA tests using electro-chemoluminescence technology which is very advanced standard. As part of our contribution to awareness of prostate-related conditions and care, we have conducted free PSA testing for over 500 patients since 2011. These tests are carried out as part of our annual Surgical Outreach Program in which over 30 candidates have also benefited from subsidized prostate surgeries since then. Kelina was the first hospital in West Africa that started doing Holmium Laser Enucleation of the Prostate (HoLEP). Patients can go home the same day, sometimes, after HoLEP. Many of these patients came at a time they could benefit from our annual surgical outreach programme. We are rounding up this year’s programme on September 30, 2020.
These are some of the factors responsible for elevation in PSA levels. Before declaring that you have cancer of the prostate, because you have done PSA on your own and the level was said to be high, please see a Urologist for proper assessment.
For more information about these programs, reach out to Kelina Hospital Service Managers on 0701 683 7070 or the Surgical Aid Program liaison on 0708 869 7154.