Secreted by prostate tissue. Used as a marker of its condition. Helps to identify inflammation, hyperplasia or tumor processes in the early stages.
Normal range of total PSA: up to 4.0 ng/ml
Normal range of free PSA: 15–25% of the total
Reasons for increased values: adenoma, prostatitis, prostate cancer
Reasons for decreased values: use of 5-alpha-reductase inhibitors