Revolutionary blood test for cancer will speed up diagnosis and help reduce NHS backlog – while breast cancer-cutting drug returns
- NHS research found that the ‘Galleri’ blood test detected two out of three cancers
- The test found where cancer was in 85 percent of the cases of 5,000 people
A blood test for cancer could be given by GPs to speed up diagnoses and reduce NHS backlogs, the world’s first data suggest.
An NHS study found that the Galleri blood test revealed two out of three cancers in 5,000 people who had visited their GP with suspected symptoms.
Where cancer was correctly detected, the test was able to pinpoint where the primary cancer was in 85 percent of cases.
Experts said the findings, which will be presented today at a global conference, showed scientists were one step closer to an oncology test in general practices.
The test, developed by biotechnology company Grail, looks for small fragments of tumor DNA circulating in the bloodstream.
An NHS study found that the Galleri blood test revealed two out of three cancers in 5,000 people who had visited their GP with suspected symptoms
It alerts doctors if a ‘cancer signal’ has been detected and predicts where in the body it may have originated.
The Symplify study, led by Oxford University, involved 5,461 people in England and Wales who had been referred to hospital by their GP with suspected cancer.
They gave a blood sample the day they went in for urgent standard tests to check for lung, gynecological, and upper or lower gastrointestinal (GI) cancers.
The participants were on average 62 years old, two thirds were female and just under half were current or former smokers.
A total of 368 people had cancer that was diagnosed through traditional methods such as scans and biopsies.
The test detected a cancer signal in 323 people, 244 who were diagnosed with cancer — meaning 75 percent of those who tested positive on the blood test were found to have cancer.
However, 2.5 percent of those who tested negative were also found to have cancer, according to results to be published in The Lancet Oncology.
This was equivalent to correctly identifying 66.3 percent of people with cancer, a measure known as susceptibility, and the ability to correctly rule out cancer in 98.4 percent of people without, a measure known as susceptibility. as specificity.
The test was more accurate in older patients and those with more advanced cancers.
It performed best in identifying or ruling out cancer in referred patients with symptoms suggestive of an upper GI tumor.
But a number of cancers were diagnosed in different places than the patient’s symptoms suggested.
Professor Mark Middleton, a consultant medical oncologist at the University of Oxford who led the trial, said the initial findings were promising.
He also said it was likely that the test could speed up diagnosis and that once the algorithm used was optimized “we think we can identify people who are currently being sent for invasive testing that they don’t need.”
He added, “It has the potential to diagnose cancer earlier and … to help achieve goals by reducing the total number of tests needed to diagnose cancer.”
But Lawrence Young, a professor of molecular oncology at Warwick Medical School, cautioned: “The real challenge is diagnosing those cancers that are hard to detect … and using a positive blood test to trigger other investigations, such as imaging.”
“To really trust that a negative result in blood tests means no more cancer is needed.”
And Professor David Cunningham, director of clinical research at the Royal Marsden, said the test still needed ‘refining’.
The results of another NHS study with people without symptoms are expected later this year. If successful, it could be rolled out to another million people by 2025.