Saliva Test for Prostate Cancer Detection

Better than a Blood Test

A study suggests that a home saliva test appears to perform better at predicting prostate cancer risk than current screening tests.

According to the study, the test assesses 130 genetic variants to provide a risk score for prostate cancer, the second most common cause of cancer death in men in the UK.

Prostate Cancer Detection

This so-called "polygenic risk score" was found to be a stronger predictor of prostate cancer than the standard blood test used in the NHS, which measures levels of a protein called prostate-specific antigen (PSA).

Professor Rose Eales, who led the research at the Institute of Cancer Research in London, said: "With this test, we can change the trajectory of prostate cancer. We have demonstrated that a simple and relatively inexpensive saliva test, which identifies men of European descent who are at higher risk due to their genetic makeup, is an effective tool for early detection of prostate cancer," according to the Guardian.

Since conducting the trial, dubbed "Barcode 1," the team has developed an updated version of the test based on newly discovered risk variants for men of Asian and African descent, and is evaluating this in a new study.

Advice for men over 50

Routine PSA screening is not currently offered in the NHS, but patients may be offered a PSA test if their GP suspects prostate cancer.

Men over 50 can request a PSA test from their GP, even if they are asymptomatic. Men with an elevated PSA result will be referred for further investigations, such as an MRI scan and biopsy, to screen for cancer.

The problem is that PSA tests incorrectly identify prostate cancer in 3 out of 4 men, and can detect cancers that grow so slowly that they are unlikely to be life-threatening – meaning men may undergo unnecessary MRI scans, surgical biopsies, and treatments whose side effects can include incontinence and erectile dysfunction.