- As explained above, PSA is a highly controversial topic. The statistics are solely intended to provide you with a rough idea of your risk.
- There are more accurate and exact ways of calculating the probability of cancer, which use such factors as the history of the PSA level, prostate volume, family history or other markers. But the most accurate method of excluding cancer is always a multiparametric MRI of the prostate by a specialist, independent of all markers.
- Please do not make a therapy decision for yourself based on the statistics shown here. Although the figures come from strong, sound scientific studies, for the sake of simplicity, not all parameters are taken into consideration. In addition, as explained above, the PSA level can have many causative factors, and a therapy decision can never be based on it alone.
Large studies in the last few years have come to differing conclusions regarding PSA screening (testing every man's PSA level frequently). While some studies report that PSA screening has no positive effect on the probability of death by prostate cancer (PLOCO), others come to the conclusion that it has reduced the relative death rate caused through prostate cancer by 20% (ERSPC).
This may seem confusing at first, but is understandable in light of the fact that prostate cancer tumors almost always grow slowly. Many men rather die with the cancer than from the cancer. Because of this, the benefits, especially of radical therapy, often do not outweigh the negative side effects, long-term damage and costs. Nevertheless, prostate cancer is one of the most frequent causes of death, and is not to be taken lightly.
Although other, more exact blood markers, such as Liquid Biopsy, PCA3, PHI, EDIM, AMACR, CTC, EPCA, p2PSA—contact us to get access to extended biological tests—are in the trial stage, PSA level is still the standard indicator for reasons related to cost and experience. In Germany, the level at or above which the PSA is considered elevated is 4ng/ml; in the USA, for example, 2ng/ml is considered the threshold value. This threshold value is not to be understood as a law. A PSA level of 3 would be considered suspicious for a man between 50 and 59 years of age, but not necessarily for a man between 70 and 79 years of age with a greatly enlarged prostate.
To quote a few statistics: the probability of cancer when the PSA level is between 4 and 10 is 25-40%. This means that 60-75% of biopsies would be unnecessary, especially rectal punch biopsies, which have a very low accuracy rate. On the other hand, with a threshold value of 4ng/ml, 20-40% of carcinomas in early stages are overlooked.
[Source: Roddam, Andrew W., et al.”Use of prostate-specific antigen (PSA) isoforms for the detection of prostate cancer in men with a PSA level of 2-10 ng/ml: systematic review and meta-analysis”. European Urology 48.3 (2005): pp. 386-399.]
This means that it is a question of weighing alternatives. If we set the threshold too low (e.g. 2 ng/ml as in the USA), prostate cancer tumors in early stages will be found more frequently, but more unnecessary biopsies will be performed. Because of today's highly precise and harmless multiparametric magnetic resonance imaging (MRI) though, it is definitely worth discussing whether the threshold could be set at a lower value (<=2 ng/ml).
The ratio of free to complexed (bound) PSA does not increase the diagnostic value of PSA level, but is also the subject of controversy and discussion.
If prostate cancer is suspected, an MRI is the safest method to exclude prostate cancer. "Safe" means not only that it provides statistical certainty but also that it isn’t harmful to the patient’s health.
Talk to us