A spit test, developed by London’s Institute of Cancer Research, can help detect prostrate cancer better than the conventional blood test.
The spit test assesses 130 genetic variants that determine the risk score of prostate cancer.
New Delhi: An at-home spit test can now help in predicting prostate cancer risk, better than the conventional blood test.
The test has been developed by researchers at the Institute of Cancer Research, London, and UK government healthcare centre The Royal Marsden NHS Foundation Trust, which assesses 130 genetic variants that determine the risk score of prostate cancer.
Prostate cancer is the second most common cancer among men in India after lung cancer. It develops in the prostate gland, a small gland in the male reproductive system that produces fluid for semen.
In the test, a sample can be collected at home that helps determine the genes linked to the deadly disease. While the spit test immediately recognises the risk, the current blood test accentuates further testing for cancer, based on age or ethnicity and symptoms.
The clinical trial, the findings of which are published in The New England Journal of Medicine, was conducted on the DNA of 6,142 European men between the ages of 55 and 69, an age when the risk of prostate cancer is higher.
They calculated a polygenic risk score (PRS), which is based on 130 small changes in the DNA that are linked to prostate cancer.
This score was created by analysing the DNA of hundreds of thousands of men.
Men who had the highest genetic risk, about 10% of the group, were invited for more screening tests. Out of 468 men with a high genetic risk score, 187 (or 40%) were found to have prostate cancer after undergoing MRI and biopsy.
In comparison, the usual PSA blood test only finds cancer in about 25% of men who have high PSA (prostate-specific antigen in the blood) levels.
Interestingly, 118 of the 187 men diagnosed with cancer had PSA levels that were considered ‘normal’—meaning they might not have been tested further using standard methods.
The usual blood test only finds cancer in about 25% of men who have high PSA (prostate-specific antigen in the blood) levels.
The PSA test often picks up cancers that are not dangerous and don’t need treatment. But the genetic risk score (from a saliva test) found more serious, fast-growing cancers.
In this study, over half (55%) of the cancers found using the genetic test were aggressive, compared to about 36% found using the PSA test.
The study found that the spit test was also more accurate than an MRI.
Since the test was developed in the UK, the research team has estimated that in England, the spit test could identify the genetic variation of up to 12,350 people earlier, saving the National Health Services around 500 million pounds a year.(IT)
