Multi-Cancer Early-Detection Blood Tests Do Not Reduce Late-Stage Cancer Incidence
- Multi-cancer early detection tests can significantly reduce late-stage cancer diagnoses and five-year mortality rates when added to routine screening schedules, according to a predictive modelling study published in...
- The study evaluated the impact of multi-cancer early detection testing at intervals ranging from six months to three years among adults aged 50 to 79.
- Under a fast tumor growth scenario where dwell times lasted two to four years in stage I, annual screening detected 370 more cancer signals per year for every...
Multi-cancer early detection tests can significantly reduce late-stage cancer diagnoses and five-year mortality rates when added to routine screening schedules, according to a predictive modelling study published in the New England Journal of Medicine. Researchers found that annual screening using a single blood sample to detect multiple cancer types prevented up to 21 percent of deaths within five years compared with usual care alone.
Predicting Patient Outcomes Across Screening Schedules
The study evaluated the impact of multi-cancer early detection testing at intervals ranging from six months to three years among adults aged 50 to 79. Investigators placed particular emphasis on annual and biennial schedules. By combining published performance measures from a large case-control study with Surveillance, Epidemiology, and End Results (SEER) data from 14 United States states, the model simulated how different testing frequencies altered stage at diagnosis and patient survival.
Under a fast tumor growth scenario where dwell times lasted two to four years in stage I, annual screening detected 370 more cancer signals per year for every 100,000 people screened. This schedule resulted in 49 percent fewer late-stage diagnoses and 21 percent fewer deaths within five years than usual care. Biennial screening yielded smaller improvements, detecting 292 more cancer signals per 100,000 individuals while producing 39 percent fewer late-stage diagnoses and 17 percent fewer deaths within five years.
Contrasting Trial Findings on Clinical Utility
While modelling suggests substantial long-term benefits, a randomized controlled trial conducted in England provides a look at real-world trial endpoints. The trial enrolled 142,250 participants aged 50 to 77, assigning them in a 1:1 ratio to an intervention group receiving blood-based multi-cancer screening or a control group. After three annual screening rounds, researchers reported no significant difference in the incidence rate of stage III or IV cancer among 12 prespecified cancer types between the intervention and control groups, with an incidence rate ratio of 1.03.
However, the trial identified a key secondary endpoint result worth noting. The incidence rate ratio for stage IV cancer alone after three screening rounds stood at 0.86, pointing toward a potential shift away from the most advanced diagnoses. Less than 1 percent of trial participants experienced trial-related adverse events, and none of those events were serious, according to the findings funded by Grail under trial identifier NCT05611632.
Efficiency and Future Trial Directions
The predictive modelling analysis also highlighted trade-offs between screening intervals regarding efficiency and positive predictive value. Biennial screening demonstrated a higher positive predictive value at 54 percent compared with 43 percent for annual screening. Furthermore, biennial testing proved more efficient per 100,000 tests in preventing deaths within five years, yielding 132 prevented deaths compared with 84 for annual testing, although annual screening prevented a higher total number of deaths per year.
Study authors noted that real-world evidence regarding multi-cancer screening intervals remains limited, making modelling a necessary tool to estimate potential benefits under ideal assumptions. Investigators emphasize that further follow-up is warranted to determine how findings for late-stage cancers evolve over time and to establish definitive timescales for future clinical trials.