Why is PSA elevated in prostate cancer?
The PSA is very organ-specific, it is formed exclusively by the prostate. In most changes of the prostate, the PSA level is elevated, as for example in the frequent benign prostatic hyperplasia (BPH). However, this does not necessarily have to be the case; there are also prostate changes without suspicious PSA levels. Prostate carcinoma is one of these changes, which in principle can, but need not, be accompanied by an increase in PSA. Nevertheless, the higher the PSA level, the more likely it is that the prostate gland will change.
How useful is the PSA value as a precautionary factor?
Since the PSA level is only specific for the organ prostate, but not for certain diseases such as prostate carcinoma, its determination for cancer screening is very controversial. The PSA level is not a tumor marker, an elevated level is never proof of prostate cancer and can only give an indication or substantiate an existing suspicion. There is also no threshold value above which a malignant event such as cancer can definitely be assumed; higher values only increase the probability of the presence of prostate cancer.
The PSA value alone is therefore insufficient for screening. Men aged 45 years and older should have regular screening for prostate cancer, which consists of a medical history, a general examination and the prostate palpation examination, called DRU. If there is a suspicion of or an increased risk of prostate cancer, the PSA level should be determined according to the guidelines of the German Cancer Society.
In this case, the determination is then also a benefit of the health insurance.Depending on its amount, the following recommendations apply to men over 45 years of age with a life expectancy of at least 10 years: PSA < 1 ng/ml: check every 4 years PSA 1-2 ng/ml: check every 2 years PSA > 2 ng/ml: check once a year
- PSA < 1 ng/ml: check every 4 years
- PSA 1-2 ng/ml: check every 2 years
- PSA > 2 ng/ml: control once a year
Ideally, the age of the patient, the prostate volume and the rate of PSA increase should always be taken into account. In addition, by additionally determining the free PSA, the PSA quotient can be determined, which is calculated as the proportion of fPSA to tPSA: PSAQ = fPSAtPSA. The proportion of free PSA should be above 15%, since for reasons unknown so far the fPSA in prostate cancer is decreasing. The PSAQ is therefore somewhat more specific for prostate cancer than the pure PSA value, but is also not conclusive.