While I am NOT an expert I have just returned from my latest Urology appointment and have friends who have had surgery.
As Jay and others have written the key is consistency in the lead up to a PSA blood test. Riding a bicycle can and does alter the results so it is best not to ride for a minimum of two days before. Other forms of exercise may also have an effect so two days of being a couch potato may be a good idea.
The NHS and other authorities have set levels where doctors have to become concerned. The kicker is that these levels are all different and the bad news is that you may have cancer with virtually any value. I went private and was told by the doctor that he had patients with raging cancer with a PSA of less than one and other patients with PSAs of over 50 with no cancer.
If you search for papers about PSA and Prostate Cancer you will find tens of thousands. Many trying and failing to make the cancer diagnosis more accurate.
Given that 80% of 80 year olds have Prostate Cancer and many men die with but not of prostate cancer it is likely that if you are male you will be introduced to the Urologists Handshake, more properly known as a DRE (Digital Rectal Examination), so time in your life. The next tool is the MRi from which you will get a PiRads score between 1 and 5. 4 and 5 are not good news and lead to a biopsy which is 20 minutes or so of awfulness. If cancerous cells are detected you will be given a Gleeson Score which is two digits and again higher numbers are bad news. An aggressive cancer may be treated by a Radical Prostatectomy often using a Da Vinci machine/robot, or radiation in some form. Hopefully this removes all the cancer but it may have some unpleasant side effects with incontinence and sexual disfunction being the head line acts.
Generally the older you are when prostate cancer is diagnosed the more likely it will be of a slow growing non aggressive type which will probably just be monitored.
A good source of friendly information may be found here :
https://thepenisproject.podbean.com/ and here :
https://www.bbc.co.uk/sounds/play/m0021b94
Please remember I am NOT an expert, I'm just someone who is in the machine waiting for my second MRI.
best wishes and good luck
S