New, small-scale research has revealed evidence of cancer three years earlier than the disease would otherwise be diagnosed. Known as the multicancer early detection or MCED test, it studies genetic material shed by tumours into the bloodstream.

According to scientists, who published the study in the journal Cancer Discovery, the test revealed cancer DNA that was circulating in the blood of a few patients up to three-and-a-half years before their cancer diagnosis was done. “Detecting cancers years before their clinical diagnosis could help provide management with a more favourable outcome,” said senior researcher Dr Nickolas Papadopoulos, professor of oncology at the Ludwig Center at Johns Hopkins in Baltimore. “Of course, we need to determine the appropriate clinical follow-up after a positive test for such cancers,” he added in a news release.

According to researchers, they assessed blood samples collected for a large-scale, federal-funded research project focused on heart disease. They used the test to thoroughly look into more than 20 participants who were diagnosed with cancer within six months of providing blood samples against similar participants who did not develop cancer.

The results said around eight of the total samples were positive on the MCED test, and those eight people were diagnosed with cancer within four months of providing the sample, results showed. The diagnosis revealed three of the participants had colon cancer, and one each had pancreatic, rectal, lung, breast, or liver cancer. Five of the eight patients eventually died from their cancers.

However, scientists further investigated blood samples for six of the eight patients that had been drawn three to three-and-a-half years before their detection of the deadly disease. It was then found that tumour-shed DNA in four of those earlier samples, which indicated that those patients’ cancers could have been caught years earlier. “This study shows the promise of MCED tests in detecting cancers very early and sets the benchmark sensitivities required for their success,” senior researcher Dr Bret Vogelstein, professor of oncology and co-director of the Ludwig Center at John Hopkins, said in a news release.

However, according to researchers, more studies with larger samples are required to confirm these findings, even though the present results indicate that this sort of blood test could catch cancers at an earlier and more survivable stage. “The focus of our study was not to demonstrate the performance of a new MCED test but rather to demonstrate how early [bloodborne cancer DNA] can be detected by any MCED test,” researchers wrote in their paper.

Researchers also noted that detecting cancers way earlier than the final diagnosis will require blood tests that are 50 times more sensitive than those used to detect cancers six months prior to diagnosis. “Establishing technologies for achieving this benchmark is a worthy future goal,” the team wrote.