Normal range of prostate health index

The normal reference range of the prostate health index (phi) commonly used in domestic clinical practice is <27. When phi≥27, it indicates that the risk of prostate cancer is 3-5 times higher than that of the general population. It is usually recommended to further improve the risk assessment.

Speaking of it, I just met a very typical patient last week, 54-year-old Brother Wang. The unit physical examination showed that the total PSA was 6.8ng/ml, which happened to be stuck in what everyone often calls the "grey zone." He was so scared that he checked Baidu for half the night. The next day, he came to the clinic with the phi report in hand, and the first thing he said was "Doctor, do I have cancer?" I took the report and looked at it, phi was 24.2, and told him that there was a high probability that it was nothing. He still didn’t believe it, and insisted on asking me to order a puncture. Finally, I persuaded him for a long time, and asked him to go back and stop drinking and riding a shared bicycle to commute. When I checked again three weeks later, the phi dropped to 19, which was a false alarm.

However, this critical value of 27 is not a hard standard that is universally applicable. The academic community has always had different opinions on the cutoff value of phi: some cohort studies in Europe and the United States set the cutoff value at 30 because the local population has a higher incidence of prostate cancer, believing that this can reduce more unnecessary invasive examinations; and domestic studies on people in Jiangsu, Zhejiang, and Guangdong and Guangxi in recent years show that for people over 60 years old with no urinary discomfort and no family history of prostate cancer, if the cutoff value is relaxed to 29, the specificity of screening can be increased by about 12%. To put it bluntly, different regions and laboratories will adjust the reference range according to the characteristics of the people they treat. When reading the report, just look at the reference value marked on the report form first. Don't scare yourself by hard-carding the universal standard of 27.

There is another piece of trivia that many people don’t know: some small actions before checking phi can easily make the results “falsely high”. Last month, there was a 28-year-old young man who had a physical examination at work that included prostate-related items. His phi soared to 31. When he came to register with the report, his face turned pale. When I asked, I found out that he had just ridden a mountain bike to a country park with a friend for 2 hours the day before the physical examination. His prostate was pressed all the way by the saddle. It was strange that the indicator did not go up. I asked him to go back and rest for 10 days before checking again. The value dropped directly to 22. Nothing happened. Generally speaking, it is best not to have sex, do not have invasive procedures such as digital rectal examination and cystoscopy, and do not ride bicycles or motorcycles for a long time three days before the PH test, otherwise the results will not be in vain.

Of course, this does not mean that as long as the value is below 27, it is absolutely safe. Last year I met a patient whose phi was only 26.3, which is a little lower than the critical value. However, his brother had prostate cancer just two years ago, and the ratio of fPSA to total PSA was only 0.08. I still persuaded him to do a puncture, and it was finally found that it was low-risk prostate cancer. Because it was discovered early, he underwent minimally invasive surgery and now he is recovering well, and he does not even need to undergo follow-up endocrine therapy. Personally, I pay more attention to the dynamic changes of phi in clinical practice. If you checked it was only 15 six months ago, and this time it suddenly rises to 26, even if it is not the critical value, you should be careful and review it regularly. After all, the risk changes dynamically, and you cannot rely on a number to stop it.

To put it bluntly, the prostate health index is essentially a risk scale for doctors to refer to. It has never been a "sentence sheet" - just like the tire pressure of your car has alarmed, it may not necessarily be a puncture, it may just be shrinkage due to cold weather, or it may be just a small nail stuck in. You will find out after you go to the tire repair place to check. Don’t panic when you get the report. It’s much more reliable to see a urologist combined with your age, symptoms, family history, and other examination results such as MRI results than to speculate on the numbers yourself.