Total prostate-specific antigen is the sum of free prostate-specific antigen and bound prostate-free antigen.
About 10-20% of the specific antigen is present in the free form and the rest is present in the bound form, and the sum of the two is called the total prostate-specific antigen. Therefore, clinical prostate tumor marker tests can generally be divided into three items, namely, total prostate-specific antigen, free prostate-specific antigen, and the ratio of the two.
Serum prostate-specific antigen is a prostate tumor marker, and if serum total prostate-specific antigen exceeds 4 ng/mL, it suggests the possibility of prostate tumor. However, there are many factors affecting the prostate-specific antigen, such as prostatitis, rectal fingerprinting, prostate massage, and prostate surgery, all of which may cause different degrees of elevation of the total prostate-specific antigen.
If elevated total prostate-specific antigen is found in the serum, prompt medical attention is required, and if necessary, prostate aspiration biopsy is needed to clarify the presence of prostate cancer.
An MRI of the prostate and, if necessary, ultrasound-guided prostate aspiration biopsy are recommended to further clarify the diagnosis.