It’s estimated that one in six Australian men will have prostate cancer by 85. Scientists in the UK believe a spit test could improve early detection.

According to Cancer Council, ‘prostate cancer is the most common cancer affecting Australian men (after non-melanoma skin cancer)’, and screening tests can save lives.

Now, UK scientists claim early diagnosis could be as easy as spitting into a tube.

Testing saliva for cancer

Polygenic risk scores predict a person’s risk of getting a disease by assessing variants in several genes. 

As part of a study published in The New England Journal of Medicine, a team from London’s Institute of Cancer Research calculated the polygenic risk score of men aged between 55 and 69 through DNA testing to determine which of them were born with a high risk of developing prostate cancer.

The test looks for 130 DNA mutations that could increase the risk of developing prostate cancer, rather than detecting prostate cancer in the body. 

745 men were flagged as high risk, and 468 of them agreed to further testing through a biopsy and MRI scan. 

187 participants were found to have prostate cancer, and 55 per cent of them had ‘cancer classified as intermediate or higher risk’, and were directed to treatment. 

The researchers believe the saliva test may be better at detecting prostate cancer than other common tests, writing, ‘the percentage [of participants] found to have clinically significant disease was higher than the percentage that would have been identified with the use of PSA or MRI.’

Experts say more research is needed

The test hasn’t been proven to be lifesaving yet, and still needs more extensive testing.

Professor of Stem Cell Sciences at King’s College London, Dusko Ilic said the test is “promising”, but “only modestly” improved detection of the cancer.

The research only involved people of European heritage, so it needs to be expanded to include a wider demographic. 

Professor of Oncogenetics at The Institute of Cancer Research, Ros Eeles said, “With this test, it could be possible to turn the tide on prostate cancer. We have shown that a relatively simple, inexpensive spit test to identify men of European heritage at higher risk due to their genetic makeup is an effective tool to catch prostate cancer early.” 

“Building on decades of research into the genetic markers of prostate cancer, our study shows that the theory does work in practice – we can identify men at risk of aggressive cancers who need further tests and spare the men who are at lower risk from unnecessary treatments.”

Early detection of life-threatening prostate cancers is crucial, so the new test is encouraging.

For cancer information and support call Cancer Council’s 13 11 20 Information and Support line.