What is the PSA value?
The PSA value indicates the level of prostate specific antigen (PSA) in the blood. PSA is a protein that is produced by the gland cells of the prostate (prostate gland) in men. An elevated level can indicate a disease of the prostate gland, such as inflammation or prostate cancer.
The determination of the value can be carried out in the context of the cancer progeny. However, this is considered controversial, as elevated values are often present without a disease worthy of treatment (false positive result). In the case of elevated values, it is often recommended to take a sample from the prostate in order to investigate the suspicion of cancer.
When is the PSA value determined?
In Germany, every man over 45 years of age is entitled to an annual examination of the prostate gland as part of the early detection of cancer. In addition to a palpation of the prostate with a finger through the rectum, the doctor asks the patient about possible symptoms that could indicate prostate disease or cancer. As long as no abnormalities are found during these cancer screening measures, the PSA level is not usually determined.
If the patient still wishes to have the PSA level determined by taking a blood sample, this is usually only possible at the patient’s own expense. The situation is different if the palpation examination and the medical consultation result in conspicuous findings that should be further clarified. In this case, the PSA value is usually determined within the scope of further diagnostics. Other circumstances that make a determination of the PSA level necessary are check-ups, for example after the treatment of prostate cancer.
What does the PSA value say?
The PSA level is a specific organ marker for the prostate, i.e. an increase always starts from the prostate. However, it is not a cancer marker, which means that an elevated value may be an important indication of the presence of cancer, but is by no means proof of it. Conversely, normal PSA levels can also indicate the presence of prostate cancer.
In the case of elevated PSA values (above 4 nanograms per milliliter: >4ng/ml), a diagnostic clarification of the cause of the elevation should be performed. Often, for example, a benign enlargement of the prostate is present, but in many cases it should be treated in time to prevent or alleviate symptoms. In the case of elevated values, additional laboratory tests are performed.
For example, the ratio of free PSA (fPSA) to total PSA can be determined. Part of the PSA is bound to another substance in the blood and another part is free. If the proportion of fPSA is below 15%, prostate cancer is likely to be the cause of the increase.
The lower the percentage, the higher the probability. Furthermore, by determining the PSA level at different points in time, the PSA doubling time can be calculated. In the case of very long doubling times (over 24 months) and rather low PSA values (>6 ng/ml), no immediate clarification is necessary. In the case of shorter doubling times and higher values, a sample should be taken from the prostate by means of a punch biopsy in order to detect or rule out cancer at an early stage.
