Son is 23 - please help me understand these numbers

My Son had blood work a couple of months back and he just sent them to me as some of it was off-kilter but what stuck out to me was his PSA. This is what it said:

TOTAL PSA 0.5:- NORMAL
FREE PSA - 0.1: NORMAL
% FREE PSA - 20L: OUT OF RANGE

How can the top 2 numbers be normal and the % not be? What does this mean? Why didn't the doctor bring it to our attention.

Please help calm my fears. My Son is not very healthy in terms of being overweight and eating horribly.

In a 23 year old, prostate cancer is not only unlikely to exist, as Andrew said, it's unheard of, as far as I know. I wouldn't give it a second thought, but yeah, I'd ask the doc the reason for a PSA test being given to a 23 year old.

Keep in mind that he's taking a test that's normally designed for people twice his age. So I think a lot of the things that they look for to be in a normal range would not even apply to him. And even for older guys, PSA by itself can be indicative of many things, many of them of no real worry. At age 23, I'd guess that he has a better chance of being hit by lightening (1 in 700,000) than having prostate cancer.

That said, I'm sorry to hear about his hormone and thyroid problems, but that would be where I would focus on with his bloodwork. Good luck to the two of you.

The ratio of free PSA to total PSA is useful for determining the probability that a middle-aged man with a mildly elevated total PSA has cancer. There are a number of factors that can cause an elevated PSA reading and the free PSA test relies on the fact that PSA produced by prostate cancer tends to be bound to serum proteins while PSA produced by, say, inflammation or an infection is more likely to be unbound. The test says, in effect, "there is a lot of extra prostate selective antigen here, let's try to figure out where it came from." But your son's total PSA reading is normalish -- no extra PSA to worry about -- and I don't think the test should have been run or the results reported. That test is intended for men whose total PSA is in the range 4-10 (eight to twenty times your son's result) and for men who are twice or three times your son's age.

My only advice for your son would be that the next time he gets a PSA test (which shouldn't be for about twenty years) he should avoid bicycle riding and sex for 48 hours before he has the blood drawn since those things can cause a slightly elevated reading which would worry his mom.