Prostate cancer tests common in Stockholm
A new study from Karolinska Institutet shows that around two thirds of men in the Stockholm region over the age of 50 have undergone PSA testing for prostate cancer, and that the test is especially common in the 70-79 age group. According to the scientists, the tests are being made despite the fact that men of this age have little to gain from the early discovery of prostate cancer.
"Prostate cancer develops slowly, and for many men the disease is never life-threatening, while treatment can cause considerable suffering for the patient in the form of incontinence and impotence," says Dr Tobias Nordström, physician and one of the researchers involved in the study. "However, the early discovery of prostate cancer using PSA tests also saves lives, and this creates an ethical dilemma for the health services."
PSA, or prostate specific antigen, is a protein produced by the prostate gland (located just below the bladder) and that is also normally found in small quantities in the blood. By measuring blood levels of PSA, doctors can discover early-stage prostate cancer. However, other changes in the prostate can also induce a rise in PSA. A large European study has already shown that population-based PSA screening reduces mortality from prostate cancer; but whether PSA screening is to be introduced remains a moot point and in Sweden, men are recommended to have themselves tested only after having discussed the pros and cons of screening with a doctor.
In the present study, which is published in the scientific periodical European Urology, researchers have analysed effectively all PSA tests carried out in the Stockholm health authority from 2003 to 2011. Their results show that the use of PSA tests is widespread in the Stockholm region and that approximately two thirds of men between 50 and 79 have been tested at least once in the past nine years; this breaks down as 46 per cent in the 50 to 59 bracket, 68 per cent in the 60 to 69 bracket and 77 per cent in the 70 to 79 bracket.
Number of PSA tests increased
Looking at the past 12 months, the researchers found that 17 per cent of the 50 to 59 age group had been tested, 27 per cent of the 60 to 69 group, and 31 per cent of the 70 to 79 group; and that the absolute number of PSA tests carried out increased from 2003 to 2011. Their results also showed that repeat tests were common regardless of the results of previous tests, with over one in three men between the ages of 40 and 89 returning for a second test within 26 months despite the first yielding a PSA score of under 1 ng/ml blood.
"Half of men in their 60s have such a low PSA score, which is associated with a very low risk of life-threatening prostate cancer, even after a long-term follow-up," says Dr Nordström. "This means that we can question such frequent testing for these men. We can also question frequent PSA screening for older men as they have less to gain from the early discovery of small tumours, but much to lose from the side-effects of treatment."
The study was financed with grants from the Strategic Research Programme in Cancer (StratCan) and the Linnéus Centre for Breast and Prostate Cancer, both at Karolinska Institutet, the Swedish Research Council and the Swedish Cancer Society. Next January the team plans to embark on a follow-up study (STHLM3) in order to test new, improved diagnostics for the earlier and safer discovery of prostate cancer.'
Publication
Prostate-specific antigen (PSA) testing is prevalent and increasing in Stockholm County, Sweden, Despite no recommendations for PSA screening: results from a population-based study, 2003-2011.
Eur. Urol. 2013 Mar;63(3):419-25