The use of the PSA examination in a screening programme for prostate cancer in the adult population is a debated issue. Two major studies dating back to 2009 have given conflicting results on the effectiveness of the test in reducing specific mortality from prostate cancer. A recent study is now re-launching the issue and pointing out the usefulness of the study to counteract the most harmful effects of cancer. Meanwhile – as Dr. Nicolò Buffi, urologist at Humanitas, recalls – the research is going on alongside the PSA with new powerful tools for early diagnosis.
The test
PSA stands for Prostatic Specific Antigen, a specific protein produced by prostate cells. Testing PSA in a blood sample measures blood levels: Being higher in men with prostate cancer, the values of this antigen are also higher. In 2009, in the New England Journal of Medicine, two large multi-center and randomized studies were published, one in the United States (the PLCO-Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial study) and one in Europe (the ERSPC-European Randomized Study of Screening for Prostate Cancer). However, only the latter concluded in the sense of a reduction in mortality from prostate cancer for patients under examination for PSA.
Recently researchers from the University of Michigan and the National Cancer Institute (USA) have published in the Annals of Internal Medicine a study that reviewed the data from these two studies. The authors considered the differences in the protocols followed by previous research and concluded indicating a reduction in mortality of between 25% and 32% due to PSA testing.
In conclusion, the team suggests a revision of the guidelines for the diagnosis of prostate cancer in the light of the results of this research: “The PSA test remains one of the main tests to detect the presence of prostate cancer, which is still validated by the European Society of Urology,” recalls Dr Buffi. However, there is a gray scale regarding its results, which require the interpretation of a specialist and his assessment for the need for further examination. Moreover, it is not yet expected to be routinely used.
Beyond PSA
The issue of screening with PSA is still controversial. In any case, in recent years, important novelties have been introduced that could overcome the centrality of PSA: “The main innovations are the multi-parametric prostate resonance and studies on its association with the BRCA2 gene, i.e. family history with prostate cancer and breast cancer,” explains the specialist.
There are important steps forward both in the understanding of the genetic profile of the risk of developing cancer and on the radiological front. They are all tools that will provide more information about prostate cancer and the most appropriate and timely treatment beyond the PSA examination,” concludes Dr Buffi.