Is It Possible to Detect Prostate Cancer With a Saliva Test?

Prostate cancer is one of the most frequently seen types of cancer in men and affects millions of men every year. Early diagnosis is of vital importance in terms of the disease being treated successfully. So can the saliva test, which has come onto the agenda recently, really detect prostate cancer? What do the scientific data say about this? Now let us examine the place of the saliva test in the diagnosis of prostate cancer in the light of current research.

What Is the Saliva Test and How Does It Work?

The saliva test allows genetic analysis to be carried out with a saliva sample taken from an individual suspected of being ill. These tests create a personal risk profile by examining specific genetic variations in the person's DNA (particularly SNPs - single nucleotide polymorphisms).

In this new test developed for prostate cancer, more than 130 genetic variations are analysed and a "polygenic risk score" (PRS) is calculated. This score shows the person's probability of developing prostate cancer during their lifetime. The test promises hope particularly for the early diagnosis of individuals who show no symptoms at all but are in the high-risk group.

The BARCODE 1 Study: Facts With the Power of Science

The study called BARCODE 1, conducted by the UK-based Institute of Cancer Research (ICR), is one of the largest and most comprehensive studies in this field. In the study, carried out on 6,142 men of European origin, the genetic risk scores obtained from saliva samples of individuals aged 55-69 were analysed.

• Prostate cancer was detected in 40% of the men with the highest 10% risk score.
• In more than half of this group (55.1%) aggressive types of cancer were seen.
• This rate is considerably above that of the aggressive cases detected with traditional PSA tests (35.5%).

These data have revealed that saliva tests may be more accurate in detecting aggressive prostate cancers.

Comparison With the PSA Test: Why Does the Saliva Test Stand Out?

For years the most widely used method in prostate cancer screening has been the PSA (prostate specific antigen) test. However, the PSA test can lead to false positive results or unnecessary biopsies in many men. In addition, because it can also reveal slowly progressing cancers that do not require treatment, it can complicate treatment decisions.

The saliva test, on the other hand, because it focuses directly on the individual's genetic risk, provides a more accurate risk assessment. It is more advantageous than PSA particularly in detecting types of cancer that follow an aggressive course. This situation can play a critical role in preventing problems such as overdiagnosis and overtreatment.

The Advantages of the Saliva Test

• It is non-invasive: it does not require a blood test or biopsy; the analysis can be carried out with a saliva sample alone.
• It offers personalised screening: a risk assessment is made according to each individual's genetic profile.
• It targets aggressive cancers: it is more accurate in detecting cases requiring treatment rather than slow-course cancers.
• It offers a forward-looking screening strategy: it provides a risk prediction before the symptoms of the disease emerge.

Does It Have a Place in Clinical Practice?

Although it has not yet passed into widespread clinical practice, genetic screenings based on the saliva test have begun to be evaluated within the scope of pilot programmes in many countries. A new study called TRANSFORM, launched after the BARCODE 1 study, is investigating the validity and effectiveness of this test in different ethnic groups.

These tests are expected to be integrated into prostate cancer screening guidelines in the period ahead. Particularly in individuals with a family history of prostate cancer, the use of such genetic tests can create an important transformation.

Who Can Benefit From This Test?

• Those with a family history of prostate cancer
• Men over the age of 55
• Individuals with contradictory results on the PSA test
• Those seeking a more personalised approach to screening

This test is not a diagnostic tool; it is a screening method that determines risk. For this reason, in individuals whose saliva test result is high, the diagnosis must be confirmed with methods such as advanced imaging (MRI) or biopsy.

Could It Be the Screening Method of the Future?

The saliva test is opening the doors to a new era in determining the risk of prostate cancer. Thanks to genetic analysis, individuals' probability of developing prostate cancer can be assessed more clearly and, particularly, cancers following an aggressive course can be caught at an early stage. Its offering a less interventionist and more targeted approach than the PSA test may make this test more widespread in the years ahead.

However, it must not be forgotten that the most appropriate screening method for each individual must be determined in line with their personal health history, genetic make-up and the doctor's opinion. It must not be forgotten that saliva tests are a complementary tool supporting the decision-making processes of specialist physicians.

Warning: this content is for information purposes. If you have any health concerns, without fail consult a urology specialist.