What does total prostate specific antigen mean?

Prostate specific antigen ( PSA) is produced by the metabolism of male prostate squamous epithelial cells. It belongs to the kininase family of proteins and exists in male prostate tissue and semen. It is very rare in normal human blood cells. Prostate specific antigen exists in three main forms in blood cells: blood pressure dispersed prostate specific antigen (fPSA), accounting for 10% to 30% of total prostate specific antigen (tPSA);

The nitric oxide synthase (PSA-ACT) produced by the fusion of male prostate-specific antigen and α1-antichymotrypsin in the blood; the nitric oxide synthase (PSA-α2M) produced by the fusion of male prostate-specific antigen and α2-macroglobulin. The latter two are called composite male prostate-specific antigen (cPSA). The key endocrine system of male prostate-specific antigen is to prevent semen from coagulation, and it has a very high tissue organ specificity. It is the preferred marker for diagnosing prostate cancer at this stage.

Clinical manifestations of prostate-specific antigen in men

If blood cell tPSA and fPSA increase, while fPSA/tPSA decreases, then prostate cancer is considered, in order to improve the specificity and accuracy of the diagnosis. Prostatitis, prostatic hyperplasia, nephritis, male prostate cysts and urinary system diseases can also be seen with a slight increase in blood cell tPSA and fPSA. When tPSA or fPSA is used independently to diagnose prostate cancer, the influence of good male prostate diseases cannot be eliminated.

Reference range of male prostate specific antigen standard values

Total male prostate-specific antigen (tPSA): <4.0ng/ml; dispersed male prostate-specific antigen (fPSA): ml; fPSA/tPSA: >0.25.

Frequently Asked Questions about Prostate Specific Antigen in Men

1. Before collecting blood samples, avoid prostate massage, male prostate puncture biopsy, rectal digital examination, indwelling catheter, and actual ureteroscopy.

2. PSA values ​​measured by different methods are different and cannot be used interchangeably.

3. For prostatitis, PSA should be measured 8 weeks after symptoms subside.

4. Long-term cycling can easily cause an increase in blood cell PSA levels.

5. Hormone therapy will affect the expression of PSA and may reduce PSA levels.

6. Blood samples should be filtered and frozen within 3 hours of collection and should not be frozen for more than 24 hours.

7. Age has an impact on blood cell PSA levels, which tend to increase continuously with age.

Male Prostate Specific Antigen Screening Group

1. Men aged 50 years and above with lower urinary tract symptoms.

2. Men with a family history of prostate cancer.

3. Men with abnormalities in digital rectal examination, clinical symptoms (such as fractures, bone pain, etc.) or abnormalities in imaging diagnosis.

4. Patients who have already been diagnosed with prostate cancer need to have their blood cell PSA checked regularly at any time after treatment.