what is psa % free
A follow-up test that measures free prostate-specific antigen (free PSA) may be used to see if a prostate biopsy should be done to check for cancer. Free PSA is the percent of prostate-specific antigen that is not attached to proteins in the blood. The lower a man's free PSA percentage, the more likely he is to have prostate cancer. A man with a total PSA between 4 and 10 ng/mL may have a test to find out his free PSA, to see if cancer is likely to be present.