PSA test halves mortality rate
Despite its success story since its routine introduction in the early 1980s, the PSA test for the early detection of prostate cancer is now more than ever the subject of critical discussion. This was prompted by two studies published last year in the New England Journal of Medicine. While the European study demonstrated that mortality in men whose blood was tested for prostate specific antigen (PSA) decreased by 20 percent, the American study found no significant difference between tested and untested men.
A third study recently published in the professional journal "Lancet Oncology" now shows that the PSA test was wrongly attacked. Swedish physicians from the University of Gothenburg examined the benefits of the PSA test on 20,000 men aged 50 to 65 years of age at the beginning of the disease, the course of which was documented over 14 years. One half was invited to the PSA test every two years, the other half served as a control group and did not take any tests. The men underwent a biopsy if the PSA was abnormal.
PSA test can save lives
The results are clear: with a total of 0.9% (no PSA test) versus 0.5% (PSA test), a statistically significant reduction in mortality (mortality) was observed. After 14 years, only about half as many men in the PSA group died from prostate carcinoma as in the comparison group. The Swedish study clearly proves that PSA screening can actually save lives,"says Dr. Derakhshani, urologist at the West German Prostate Center in Cologne. However, it is not yet clear from the study data whether the lower mortality rate has an impact on the overall survival of men. According to Derakhshani, in order to see what changes will occur over time, an even longer follow-up period is required.
Minimizing the side effects of treatment
Nearly 300 men must be invited to the early diagnosis and at 12, prostate cancer must be diagnosed in order to prevent a death from suffering,"said Dr. Neal, head of the study. There is still a risk of overdiagnosis, which means that tumours that are not life-threatening are detected. However, this is considerably lower than in previous studies. Thus, the number of so-called "Number Needed to Treat" is comparable to recognized methods for the early detection of breast cancer.
In addition, not every man who receives the diagnosis of prostate cancer has to undergo a radical removal of the prostate, Dr. Neal continued. The focus in the treatment of prostate cancer patients should be on achieving optimal cure rates with minimal side effects. Modern radiation therapy methods such as brachytherapy are particularly suitable for this purpose. In contrast to radical removal of the prostate, the prostate gland remains intact. The ultrasound-guided introduction of radioactive pencils (seeds) directly into the prostate gland destroys the tumour and at the same time protects the surrounding tissue. In some cases, it is even sufficient to keep an eye on the cancer and monitor it closely (active monitoring).
Neal DE.: PSA testing for prostate cancer improves survival-but can we do better? Lancet Oncol. 2010 Jun 30.