‘Holy grail’ of cancer testing

Anew blood test is able to detect 10 types of cancer several years before a person displays more obvious symptoms, scientists say. The breakthrough has been hailed as a major step towards the “holy grail” of curing cancer after trials found that the simple procedure to identify DNA markers worked with up to 90% accuracy.

Experts said the findings could pave the way for an almost universal screening programme that could detect warning signs of the disease, vastly improving survival chances.

US scientists found that the simple test was able to identify genetic traces of cancers, including those that are notoriously hard to detect, such as pancreatic and ovarian disease. It looks for fragments of DNA released into the blood by fast-growing cancer cells.

Lead author Dr Eric Klein, of the Cleveland Clinic in Ohio, said: “This is potentially the holy grail of cancer research, to find cancers at an earlier stage when they are easier to cure, and we hope this test could save many lives.

“Most cancers are detected at a late stage, but this ‘liquid biopsy’ gives us the opportunity to find them months or years before someone would develop symptoms and be diagnosed.”

The results come from research on more than

1 600 adults, of whom 749 were cancer-free, while 878 had been newly diagnosed with the disease.

The tests found early warning signs in the blood for 10 types of cancer with accuracy of more than 50%. The best results were for ovarian and pancreatic cancer, at 90% and 80%. Four out of five were diagnosed with liver and gall bladder cancers.

For blood cancers lymphoma and myeloma, it was 77% and 73% accurate, while correctly diagnosing two-thirds of people with bowel cancer.

The results for triple-negative breast cancer were 58% and the test also detected lung, gullet and head and neck cancers with better than 50% accuracy. It was less able to pick up stomach, uterine and earlystage low-grade prostate cancer.

Klein, whose research team also involved Stanford University, said: “Potentially this test could be used for everybody, regardless of their family history. It is several steps away, and more research is needed, but it could be given to healthy adults of a certain age, such as those over 40, to see if they have early signs of cancer.”