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Oganes E. Dilanyan
Urologist, MD, PhD

PSA blood test

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In this article

Raised PSA is a worrying symptom indicating a problem with the prostate. A blood test measuring PSA is used all over the word for early detection of prostate cancer. This is why raised PSA often warrants a prostate biopsy.

“Every male over 45 should have a PSA blood test once a year”

Recommendation by the European Association of Urology 

Common case

— To be honest, doctor, I simply don’t see the point. I have no problems in that area. I urinate normally and have a good sex life. Nothing hurts and nothing is bothering me. Why do I need a blood test? And specifically, why PSA? What is it? 
— You see, Vladimir, - I say. Prostate cancer is quite common and when spotted early is very treatable. But if it is spotted late is incurable. 
— But as I said, I have no complaints...

For any urologist his sort of conversation with a patient is a very common occurrence. But really, why bother with a prostate specific antigen blood test if nothing hurts and there are no problems with urination or one’s sex life. Why do urologists insist on performing this blood test even if the patient presented with kidney stones? The answer is simple. Early detection of prostate cancer is key to successful treatment. Radical treatment, not just prolonging life. And PSA is an indicator of how healthy the prostate is. Let’s take a look.

What is PSA?

PSA is prostate specific antigen is a protein that has a very specific function. It liquefies semen and allows sperm to swim freely.

This protein performs a very specific function in the sperm. It has nothing to do in the blood. Usually only traces or very small quantities of PSA are found in the blood: normal PSA in the blood is from 0 to 4ng/ml. nanogram is one thousand-millionth of a gram which is negligible amount. 

Raised PSA cannot be treated on its own. It is just a symptom.

Normal and raised PSA

How and why PSA becomes raised. There is only one way for it to happen, when the capillaries in the prostate become damaged. Any process that damages the capillaries, such as prostatitis, benign prostatic hyperplasia or prostate cancer will lead to raised levels of PSA in the blood.   
Digital rectal examination of the prostate, vigorous sexual activity or even constipation can also cause raised PSA in the blood due to the fact that these activities can damage capillaries of the prostate. 
This is why there are specific rules when it comes to PSA blood test. First of all, this blood test should not be performed after vigorous sexual activity and next day after a digital rectal examination of the prostate. The result will not be accurate. Secondly it is necessary to perform not just one but two blood tests, general and free PSA.
The latter is very important as this antigen is present in the blood in two forms, bound to proteins and free. It is noted that in the presence of prostate cancer the level of free PSA in the blood drops as the amount of binding protein increases.

Medicine is the most precise science after theology.

PSA blood test explained

— “Now, doctor, please explain to me why you prescribed antibiotics and a repeat blood test in a month’s time to my friend who has higher levels than me and I have to have a prostate biopsy.” – Vladimir asks with a frown having finally had all the blood tests.    
— I would have sent you to have a prostate biopsy even if your PSA levels came back as zero, - I say politely but firmly. Prostate ultrasound scan detected a hypoechoic nodule and we also found a dense area during a digital rectal examination. Your free to general PSA ratio is lower than 15%.  Even one of these markers warrants a prostate biopsy to rule out prostate cancer. 
Vladimir’s face is a mix of emotions. I guess the meaning of it straight away :”Doctor, can you repeat this in Russian?”
— Look, Vladimir, there are several markers that point to prostate disease. First one is determined by the digital rectal examination where the doctor examines your prostate via the colon. By doing this we get the information about the consistency of the prostate, it’s size, uniformity, sensitivity/presence of any pain and colon mucosa mobility. A thickened area is just what is says – a thick area in the prostate. It is often an indication of prostate cancer. Then we perform an ultrasound to make sure it is not a prostate stone. In your case we detected a hypoechoic nodule which is an area of prostate tissue that looks dark on the screen. This can also point to prostate cancer. 
— But my blood test results are almost normal! They are just slightly over the normal limit! 
—  Unfortunately, Vladimir, there are some forms of prostate cancer where prostate specific antigen levels remain within normal range. Also, let’s not forget about the free to general PSA ratio. Your free PSA levels are very low. This is another sign of prostate cancer. So, the verdict is clear – you need prostate biopsy. 
— Ok. 

I would like to be wrong. But the histology report with treble independent verification is merciless. “Small acinar adenocarcinoma detected in 5th and 6th biopsy sample with Gleason score 6 (3+3)” .
...I am so glad I insisted on Vladimir having the PSA blood test and prostate biopsy. I am not so glad that malignant prostate tumour was detected, but it was in the early stages and could be surgically removed. This made it possible for Vladimir to have surgery which rid him of prostate cancer. This is why it is very important not to ignore your doctor’s recommendations and to have all the tests before it is too late.

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