Free prostate antigen is medically known as free prostate-specific antigen (FPSA), perhaps associated with prostatitis, prostate hyperplasia, prostate cancer, etc., and needs to be analyzed in combination with total prostate-specific antigen (TPSA) to further confirm the diagnosis. If the TPSA is less than 4 nanograms per milliliter, a high FPSA is generally not clinically significant. If the TPSA is between 4 ng per milliliter and 10 ng per milliliter, then the higher the FPSA value, the less likely prostate cancer is. That is, an FPSA/TPSA between 0.15 and 0.2 is less likely to be cancerous, and a prostate aspiration biopsy is usually needed to rule out cancer when the FPSA/TPSA is less than 0.15. If the TPSA is greater than 10 nanograms per milliliter, the patient has a high chance of developing cancer and will need to be further diagnosed in conjunction with a pathology report. Patients who find that the report shows high free prostate-specific antigen should go to the urology department for further diagnosis.