Groundbreaking new blood test detects cancer early

Researchers from the United States are celebrating this week after developing a new blood test that can detect more than 50 types of cancer. The results of their research, published in medical journal Annals of Oncology on Friday, confirmed the new test is accurate enough to be rolled out as a multi-cancer screening test among people at higher risk of the disease, including patients aged 60 years or older, without symptoms.

The test, created by the Californian company Grail, also predicted with a high degree of accuracy where in the body the cancer is located, and had a low false positive rate. Some of the cancers that the test is capable of detecting include liver, pancreatic and oesophageal.

“Finding cancer early, when treatment is more likely to be successful, is one of the most significant opportunities we have to reduce the burden of cancer,” Dr Eric Klein, the study’s first author, said. “These data suggest that, if used alongside existing screening tests, the multi-cancer detection test could have a profound impact on how cancer is detected and, ultimately, on public health.”

The test involves taking a sample of blood from each patient and analysing it for cell-free DNA (cfDNA) shed by tumours into the blood. Genomic sequencing is used to detect chemical changes to the DNA, and an artificial intelligence machine has learnt which of those changes suggest cancer is present. In addition, the machine can predict where in the body the cancer is located.

To see how accurate the blood test was, the researchers looked at 2,823 people already diagnosed with cancer and 1,254 people without cancer. It detected cancer signals from more than 50 types of cancer and found that across all four cancer stages (I, II, III, IV) the test correctly identified when cancer was present in 51.5 per cent of cases.

The test detected 65.6 per cent of cancers involving solid tumours with no screening options, such as liver, pancreatic and oesophageal. For solid tumours that do have screening options, such as breast, bowel, cervical and prostate cancers, it detected 33.7 per cent.

“We believe that cancers that shed more cfDNA into the bloodstream are detected more easily,” Klein said. “These cancers are also more likely to be lethal, and prior research shows that this multi-cancer early detection test more strongly detects these cancer types. Cancers such as prostate shed less DNA than other tumours, which is why existing screening tests are still important for these cancers.

“These data add to a growing body of literature that supports the use of next-generation sequencing for the detection of cell-free DNA in blood samples as a tool for earlier detection of common cancers that account for a significant number of deaths and other health problems worldwide. In addition, a screening test that requires only a simple blood draw could provide an option for communities that have poor access to medical facilities. I’m excited about the potential impact this approach will have on public health.”

Cancer is a leading cause of death in Australia. One in two Australian men and women will be diagnosed with cancer by the age of 85.

IMPORTANT LEGAL INFO This article is of a general nature and FYI only, because it doesn’t take into account your personal health requirements or existing medical conditions. That means it’s not personalised health advice and shouldn’t be relied upon as if it is. Before making a health-related decision, you should work out if the info is appropriate for your situation and get professional medical advice.