[…] The Galleri test has been described as a potential “gamechanger” by NHS England, which is due to report results from a major trial involving 165,000 people next year. Doctors hope the test will save lives by detecting cancer early enough for surgery and treatment to be more effective, but the technology is still in development.
“I think what’s exciting about this new paradigm and concept is that many of these were cancers for which we do not have any standard screening,” Dr Deb Schrag, a senior researcher on the study at the Memorial Sloan Kettering Cancer Center in New York, told the European Society for Medical Oncology meeting in Paris on Sunday.
In the Pathfinder study, 6,621 adults aged 50 and over were offered the Galleri blood test. For 6,529 volunteers, the test was negative, but it flagged a potential cancer in 92.
Further tests confirmed solid tumours or blood cancer in 35 people, or 1.4% of the study group. The test spotted two cancers in a woman who had breast and endometrial tumours.
Beyond spotting the presence of disease, the test predicts where the cancer is, allowing doctors to fast-track the follow-up work needed to locate and confirm a cancer. “The signal of origin was very helpful in directing the type of work-up,” said Schrag. “When the blood test was positive, it typically took under three months to get the work-ups completed.”
The test identified 19 solid tumours in tissues such as the breast, liver, lung and colon, but it also spotted ovarian and pancreatic cancers, which are typically detected at a late stage and have poor survival rates.
The remaining cases were blood cancers. Out of the 36 cancers detected in total, 14 were early stage and 26 were forms of the disease not routinely screened for.
Further analyses found the blood test was negative for 99.1% of those who were cancer-free, meaning only a small proportion of healthy people wrongly received a positive result. About 38% of those who had a positive test turned out to have cancer.
Schrag said the test was not yet ready for population-wide screening and that people must continue with standard cancer screening while the technology is improved. “But this still suggests a glimpse of what the future may hold with a really very different approach to cancer screening,” she said.