The results of the Pathfinder study from health care company GRAIL show the possibilities of what’s called multi-cancer early detection screening, which finds cancers in early stages.
“The PATHFINDER study is an exciting first step towards fundamental change in the approach to cancer screening. The study demonstrated the feasibility of this paradigm and solid test performance,” said Deb Schrag, MD, MPH, chair of the Department of Medicine at Memorial Sloan Kettering Cancer Center in New York.
“Although continued public health efforts to optimize adherence to existing screening strategies that have been proven effective are critical, this study provides a glimpse of what the future may hold — the opportunity for screening using blood tests to detect various types of cancers at their earliest and most treatable stages.”
The study included 6,662 participants aged 50 years or older whose blood was tested to look for what GRAIL calls cancer signals, which were found in 92 participants. Of those, 35 were diagnosed with 36 cancers. Cancer cells send out signals to regulate growth or initiate apoptosis (the death of cells), according to the Cancer Treatment Centers of America.
“When added to standard-of-care screening, MCED testing more than doubled the number of cancers detected compared to standard screening alone,” said Jeffrey Venstrom, MD, chief medical officer at GRAIL.
Known as the Galleri test, the blood draw has been hailed as a “game changer” by the National Health Service in England, which is conducting a trial of its own.
The blood test can also identify where in the body the cancer is likely to have originated, which can help doctors confirm a diagnosis more quickly. The Pathfinder study was the first time Galleri test results were returned to health care providers to help them with follow-up diagnostic work.
Among the confirmed cancers diagnosed in the study, 71% were cancer types that currently do not have a routine screening test, and nearly half were in either Stage I or Stage II. Less than 1% of study participants received a false positive.
The results of the study were presented this past weekend at the European Society for Medical Oncology Congress in Paris. GRAIL is currently enrolling for its Pathfinder 2 study, which will follow participants over three years.
“This study was a prelude to a larger study. We needed to see how physicians would approach workup, what diagnostic odysseys we’d send patients down, and whether they’d be upset,” Schrag said at the Paris conference, as reported by Cancer Network. “People were a little anxious, but it was manageable, and it was transient. People understood the ramifications of this test, and they were a little anxious, but they managed very well.”