Normal level ~4
It is raised in 80% of patients at age 80. So, in many patients it is raised in normal circumstances
Levels increase with age
In prostate cancer, levels can rise to 100
GP’s run checks on at risk patients and do blood tests for PSA – if these are raised, then patients are referred to clinic.
If levels are raised but stable, then patients are normally monitored either every 6 or 12 months.
If levels are raised and increasing, then it is more likely to be cancer.
Things that can raise PSA

• BPH- benign prostatic hypertrophy
• Infections (prostatitis)
• Sigmoidoscopy – (trauma basically)
• Cancer

You should always examine the prostate when levels of PSA are raised.
You shouldn’t take a PSA reading within 6-8 weeks fo infection as it is likely to be raised as a consequence of the infection, and thus when it is raised, this does not tell you much useful information about cancer / hyperplasia.
When examining the prostate:

• Normal prostate – quite firm but a bit squidgy. About 2-3 fingers width. Symmetrical with a little dip in the middle.
• Enlarged prostate – still symmetrical – pretty much identical to normal prostate, but enlarged equally in all proportions.
• Suspicious nodule – not as symmetrical as normal. Has a hardened nodule on it
• Large, irregular prostate – large prostate, very hard and many nodules. Very high likely hood of malignancy

- See more at: http://almostadoctor.co.uk/content/systems/urology/prostatic-disorders#sthash.kI1f4jLB.dpuf