A blood test that could detect 50 types of cancer has delivered a “promise” in early studies, scientists said — after spotting the disease in previously healthy people.
New York scientists found 35 cases of cancer using the test, but another 57 people were wrongly diagnosed.
It was not possible to determine accuracy because the 6,000 participants were not screened at the same time as standard tests.
The Galleri blood test uses a single swab to look for a signal made by many cancers, including those that affect the breasts, lungs, and kidneys. Scientists say it shows promise in detecting some cancers early, such as pancreatic cancer, while current tests can only detect them at later stages when survival rates are reduced.
It’s available by prescription for $949 a pack, but experts say the test shouldn’t be used in place of standard screening procedures.
Scientists at the Memorial Sloan Kettering Cancer Center who conducted the study said that while the test was good, it still needed refinement. It comes just a day after President Joe Biden unveiled plans to halve the number of cancer deaths to 300,000 a year by 2042 by investing millions of dollars in developing blood tests.
New York scientists discovered 35 cases of cancer using the test, but another 57 people were wrongly diagnosed with the condition (file photo)
The study results were presented today at the annual conference of the European Society for Medical Oncology (ESMO) in Paris, France.
The trial recruited 6,621 people over the age of 50 who were otherwise healthy.
A blood sample was taken from each and passed the Galleri test to check for cancer.
How does the Galleri cancer test work?
The Galleri cancer test works by screening the blood for signs that may indicate cancer.
The developers say the test can detect more than 50 types of cancer, including those that are usually picked up at a late stage by routine screening.
It works by looking for chemical changes in fragments of genetic code — cell-free DNA (cfDNA) — that leak into the bloodstream from tumors.
Some cancer tumors are known to release DNA into the blood long before a person would begin to experience symptoms.
Galleri says it takes about 10 days to flip a test.
They add that their test should be used in conjunction with normal screening programs.
Scientists found in clinical studies that the test correctly detected cancer in 51.5 percent of cases.
The test is available on prescription in the US for about $949 per pack.
The tests work by looking for cancer signals in the blood dumped by tumors, and can pick up more than 50 types because each makes the same separate signal.
The results showed that 92 patients tested positive for cancer.
But after each of them had a routine screening, it was found that only 35 (or 38 percent of the total) actually had the disease.
Separate screening was not performed at the time to check the patients who were completely free of some cancers.
But a year after the trial, 86 more participants were diagnosed with cancer.
It wasn’t clear whether they already had the cancer at the time the test was done, or if it wasn’t present when the test was done.
Fourteen of the cancers discovered were in stage I or II — when they’re easier to treat — and seven were found in people who had cancer in the past.
One type of cancer of the circulatory system called lymphoma was most often detected (12 patients), followed by cancers of the breasts (five), blood (three), colon and rectum (two), prostate (two) and throat (two) .
There was also one case of liver, pancreatic, small bowel, ovarian, uterine, bone, plasma cell and bile duct cancers.
And one patient who tested positive using the tests was found to have both breast and uterine cancers, the scientists said.
No data was collected on whether patients’ survival rates improved due to the earlier diagnosis.
Commenting on the study, an ESMO conference publication said the test showed a “promise” in the study.
dr. Deb Schrag, the oncologist who led the study, said: “This study indicates that there is hope on the horizon for detecting cancers that cannot currently be screened, but of course much more work is needed and, with experience and greater samples, [this] will improve.
‘The tests need to be refined so that they can better distinguish tumor DNA from all the other DNA circulating in the blood.’
It comes after Biden yesterday announced a boost to his cancer moonshot program and said he plans to halve deaths over the next two decades.
To achieve this, the president said he would spend millions of dollars developing diagnostic tests for cancer. The final amount is not yet known.
The fight against cancer is personal to Biden who lost his son Beau to brain cancer in 2015.