PSA (prostate specific antigen) and digital rectal examination are the two reference examinations for the early detection of prostate cancer. But their use has been the subject of a very real scientific debate for more than twenty years, which we will explain simply, without taking sides on behalf of your doctor.
1. PSA: a useful marker, but not specific for cancer
PSA is a protein produced by prostate cells, the level of which can be measured by a simple blood test. A high level can indeed reflect the presence of cancer - but also many completely benign situations: benign prostatic hypertrophy, urinary infection, prostatitis, or even sexual intercourse or a recent rectal exam.
The threshold usually used is around 4 ng/mL, but this figure is not absolute: some men develop cancer with a PSA lower than this threshold, while others have a high PSA without cancer. It is precisely this lack of specificity that is at the heart of the controversy over routine screening.
2. Why there is no organized screening in the general population
Several large international studies, including the American PLCO trial and the European ERSPC trial, have sought to demonstrate that systematic PSA screening reduces prostate cancer mortality. The results were mixed: the benefit in lives saved turned out to be more modest than hoped, while the risk of overdiagnosis turned out to be significant — up to 50% according to some estimates.
| Notion | Definition | Why it matters |
|---|---|---|
| Overdiagnosis | Detect a cancer that would never have caused symptoms or death | May lead to unnecessary treatments and their side effects |
| Overtreatment | Actively treat a cancer that does not progress significantly | Exposes to complications without real benefit for the patient |
| Decision shared | Choice of individual screening, after informing the doctor | Approach recommended in France rather than systematic screening |
It is for this reason that the High Authority of Health and the National Cancer Institute do not recommend systematic screening for prostate cancer in the general population, but encourage an individual and informed decision, taken with one's treating physician, particularly in men with particular risk factors.
3. Who can benefit from early detection, and from when?
Despite the absence of organized screening, individual early detection, based on PSA measurement and rectal examination, can be offered after discussion with your doctor, particularly in the following men:
- ●From age 50: for men with a life expectancy of more than 10 to 15 years, without any particular risk factor.
- ●From age 45: in the event of a family history of prostate cancer or of Afro-Caribbean/African origin, two recognized risk factors.
- ●From age 40: in men carrying a BRCA2 genetic mutation, associated with a significantly increased risk.
In all cases, this approach must be preceded by clear information on the expected benefits, but also on the risks of overdiagnosis and the possible consequences of a biopsy or treatment - a time for discussion that your treating doctor can grant you.
4. Rectal examination: a brief examination, complementary to the PSA
The rectal exam allows the doctor to directly assess the volume, consistency and regularity of the prostate. A normal prostate is flexible and regular; an abnormality of consistency (hardness, irregularity) can point to cancer, independently of the PSA level. This exam, often dreaded out of apprehension, only lasts a few seconds and requires no special preparation.
⚠️ To remember from a medical point of view
Any abnormality on rectal examination, whatever the PSA level, warrants a urological opinion - the two examinations are complementary, not interchangeable.
A first PSA dosage between 3 and 10 ng/mL must be rechecked after a period of at least two weeks before considering additional examinations, because this levels may fluctuate.
Taking certain medications (5-alpha-reductase inhibitors, used in benign prostatic hypertrophy) artificially lowers the PSA level: report any current treatment to your doctor before interpreting the result.
Tips to remember:
- ●There is no organized screening for prostate cancer in France: the process is based on an individual decision, taken after discussion with your doctor.
- ●PSA is not specific to cancer: a urinary infection, benign hypertrophy or even recent sexual intercourse can temporarily raise its level.
- ●Overdiagnosis is a real and documented risk (up to 50% according to certain studies): this is the main reason why systematic screening is not recommended in the general population.
- ●Men at increased risk (family history, Afro-Caribbean origin, BRCA2 mutation) can benefit from early detection from the age of 40-45, earlier than the general population.
- ●The rectal examination lasts only a few seconds and remains complementary to the PSA: an abnormality of consistency can direct the diagnosis independently of the blood level. The Iris Prévention health check-up can help you take stock of your individual situation.
