Clinical Significance of a Multicancer Screening Trial With Stage-Based End Points.

Area of Science:

• Oncology
• Public Health
• Biostatistics

Background:

• The first randomized screening trial for a multicancer early detection test is underway, focusing on late-stage cancer incidence.
• Interpreting short-term trial results for multicancer screening policy requires careful consideration of stage-based endpoints.

Purpose of the Study:

• To estimate outcomes of a multicancer early detection screening trial.
• To provide insights for interpreting short-term trial results in multicancer screening.

Main Methods:

• A decision-analytic model simulated a population-based screening trial using registry data from England (2013-2018).
• The model incorporated three annual screenings and estimated cancer detectability 1-2 years pre-diagnosis.

Main Results:

• The model estimated 6%-23% reductions in late-stage cancer incidence over 3 years and 6%-9% reductions in 5-year cancer mortality.
• Colorectal cancer showed the largest contribution to late-stage incidence reduction (28%-39%), while lung cancer contributed most to mortality reduction (40%-42%).

Conclusions:

• The trial can achieve significant cancer downstaging within 3 years.
• Modest 5-year mortality reduction was observed, influenced by the limited number of cancer types included.
• Transparent reporting by cancer type and consideration of mortality are vital for future screening policy development.