PSA, which stands for Prostate-Specific Aantigen, is a protein produced by the prostate gland. It is present in the blood of all men at low levels, but PSA levels often rise, sometimes dramatically, in the presence of prostate cancer.(Keith Brofsky/Photodisc/Getty Images).or men under 50, healthy PSA levels will usually range between .3 and 2.5 nanograms per milliliter (ng/mL), with an average of 1.2. In the presence of cancer, PSA levels can rise to up to 160 ng/mL. Jupiterimages/Goodshoot/Getty Images. Men From 50 to 60.