Total PSA

In case the total prostate-specific antigen value is abnormal, you must find the corresponding treatment measures at the very beginning, otherwise your symptoms will become more serious, or even induce a more serious type of disease, and then you will not be able to do relevant treatment. Also, if you are diagnosed with prostate cancer and this abnormality is detected, you must do radiotherapy and chemotherapy as soon as possible.

Abnormal results: Blood PSA levels are closely related to prostate diseases and are not specific to benign or malignant prostate diseases. Even slight injuries to the prostate (such as DRE) may cause elevated serum PSA levels. Each gram of increased prostate tissue can increase serum PSA levels by 0.3 ng/ml, while prostate cancer tissue can increase serum PSA levels by 3.5 ng/ml, a 10-fold difference.

People who need to be checked: Those with a family predisposition to prostate cancer, a high-fat diet, or contact with cadmium should have regular physical examinations and PSA tests.

① Total PSA (t-PSA) in serum includes two types: the less abundant free PSA (f-PSA), with a half-life of 0.75 to 1.2 hours; the abundant complex PSA (c-PSA), with a half-life of 2 to 3 days;

②PSA is highly specific for prostate cancer, with an overall positive rate of 82% to 97%;

③The ratio of f-PSA to t-PSA has important diagnostic value. Especially when t-PSA is between 4.0 and 10.0 μg/L, the ratio of f-PSA/t-PSA in serum is 0.15, which can be used as the critical point for distinguishing prostate hypertrophy and prostate cancer. When the ratio is less than 0.15, the possibility of prostate cancer is greater. The higher the PSA concentration, the smaller the f-PSA/t-PSA ratio, and the greater the possibility of prostate cancer. In clinical practice, the ratio of f-PSA/t-PSA in serum is often used to distinguish between benign and malignant prostate tumors.

④After successful treatment of prostate cancer, it takes 2 to 3 weeks for the high PSA concentration to drop to normal levels.

Prostate cancer has surpassed skin cancer to become the most common cancer in North American men and the second leading cause of cancer-related death. PSA is elevated in most clinically significant prostate cancers and is the most important early detection indicator. Although PSA is the most commonly used method for detecting prostate cancer, benign prostatic hyperplasia and prostatitis can also result in a positive PSA result. One way to solve this problem is to detect free prostate-specific antigen.

Studies have shown that in prostate cancer patients, the vast majority of PSA is in a bound state, and the ratio of free PSA to total PSA is lower than that of normal people or patients with benign prostatic hyperplasia. Therefore, for men with abnormally elevated total PSA, testing free PSA and calculating the ratio of free PSA to total PSA can improve the specificity of screening and diagnosing prostate cancer.