CHICAGO -- Adding a multicancer early detection (MCED) blood test to standard of care did not reduce the number of cancers detected at stage III or IV across a dozen tumor types for which no screening tests are currently available, the randomized NHS-Galleri trial showed.
After three screening rounds, a nonsignificant 3% more stage III/IV cancers were detected with the addition of MCED (incidence rate ratio [IRR] 1.03, 95% CI 0.92-1.14, P=0.06), reported Charles Swanton, MD, PhD, of the Francis Crick Institute in London, during a press conference at the American Society of Clinical Oncology (ASCO) annual meeting.
However, looking at stage IV cancers only, the investigators found a reduction of 14% after three screening rounds (IRR 0.86, 95% CI 0.744-0.998), which included a reduction of 22% after the second screening round and a reduction of 26% after the third screening round. The larger reductions in stage IV cancers in incident screening rounds suggest that "with further follow-up, a benefit in terms of reduced stage IV cancers may increase," Swanton said.
In addition, there was a 16% increase in the detection of stage I and II cancers after three screening rounds (relative risk 1.16, 95% CI 1.03-1.30).
