A saliva test that is quick, economical and above all more reliable than the current standard for detecting prostate cancer. It is the promising discovery by a group of scientists from the Institute of Cancer Research in London and the Royal Marsden NHS Foundation Trust, which could mark an epochal turning point in the fight against what is now the most common male cancer in over 100 countries.
Researchers have developed a salivary DNA analysis capable of identifying men at high risk of aggressive forms of the disease, allowing diagnosis advances that could save millions of lives.
Prostate cancer, a growing global challenge
Prostate cancer represents one of the major health challenges worldwide. According to projections, the number of men who are diagnosed with this disease is expected to double by 2040, reaching i 2,9 million of cases per year. At the same time, it is estimated a 85% increase in annual deaths related to this tumor.
The key to effectively combating prostate cancer is early diagnosis. However, experts point out that the current standard blood PSA (prostate specific antigen) test has several limitations. On the one hand, it may not detect the presence of the tumor in some men who actually have it. On the other hand, it can lead to other patients needlessly undergoing treatments or further invasive tests and scans.
A more accurate and specific saliva test
The new test by British researchers, as mentioned, simply requires the collection of a saliva sample, an operation that can be completed in a few seconds. I study (that I link to you here), demonstrates how this salivary analysis is more accurate than the current PSA blood test.
“With this test it may be possible to change the fate of prostate cancer,” he said Rosalind Eeles, professor of oncogenetics at the ICR.
We have shown that a simple and inexpensive saliva test to identify men at greatest risk based on their genetic profile is an effective tool for detecting cancer early.
Ros Eeles
The test works by looking for specific genetic signals associated with prostate cancer in saliva. In the Barcode 1 study, researchers recruited over 6.000 European men aged between 55 and 69, a range in which the risk of this tumor is higher. After collecting saliva samples, the test calculated a polygenetic risk score (PRS) for each participant, based on 130 genetic variations in the DNA code linked to prostate cancer.
Results? Fewer false positives, more cases detected
In those with the highest genetic risk, the saliva test recorded fewer false positives than the PSA test, identified people with cancer who would have been missed by PSA alone, and detected a higher percentage of aggressive tumors. Furthermore, the analysis accurately identified men with prostate cancer not even shown by an MRI.
The story of Dheeresh Turnbull, 71, from Brighton, is emblematic. He was one of the first men in the world to try the saliva test, thus discovering he had prostate cancer. “I was completely shocked when I received the diagnosis, because I had absolutely no symptoms. I know I would never have been diagnosed at this stage if I hadn't participated in the study,” said Turnbull, who later underwent successful robotic surgery to remove part of his prostate.
Salivary testing for prostate cancer, future prospects and next steps
Professor Eeles said further research will be needed before the test can be widely rolled out.
Our next step will be to test the genetic markers that we have identified as associated with prostate cancer risk in different populations, to ensure that this test can benefit all men.
Ros Eeles
Given the aging population and rising life expectancy globally, experts believe it will be impossible to prevent the surge in prostate cancer cases through lifestyle changes or public health interventions alone.
That's why better testing and earlier diagnosis are a critical weapon in reducing the impact of this disease and saving lives.