Delays in Diagnosis of Early-Onset Colorectal Cancer Across the United States: A Systematic Review

Early-onset colorectal cancer is now the leading cause of cancer death among adults under 50, with delays in diagnosis cited as a potential contributor to patients being diagnosed more frequently at advanced stages than their older counterparts. Despite this, few studies have comprehensively evaluated factors associated with diagnostic delays among patients with early-onset colorectal cancer in the United States.

To synthesize factors contributing to early-onset colorectal cancer diagnostic delays in the United States using the Model of Pathways to Treatment to guide interventions that reduce diagnostic delays.

Two electronic databases were queried: Embase and MEDLINE.

Both qualitative and quantitative studies were included if they had early-onset colorectal cancer participants and a discussion of factors contributing to delays in diagnosis. Studies conducted outside of the United States, not peer-reviewed, and lacking primary data were excluded.

Patient, provider, and system-level factors contributing to delays in diagnosis across the appraisal, help-seeking, and diagnostic intervals.

Among 35 included studies, only 8 utilized qualitative methods. Most studies examined broader trends in early-onset colorectal cancer instead of evaluating a specific interval, using stage at diagnosis as a proxy for delays. Additionally, many factors affected multiple intervals, highlighting that factors are crosscutting.

Findings may not be generalizable outside the United States, given differences in healthcare financing, access, and screening practices. Using late-stage diagnosis as a proxy for delays is also debated and could confound stage-based inferences about delay. Few studies capture the subjective experiences of younger patients or the clinical reasoning and constraints providers face when evaluating symptoms.

Diagnostic delays in early-onset colorectal cancer are difficult to confine to a single interval and require system-level interventions to support earlier detection. More qualitative inquiry is necessary to identify effective interventions, including interviews that elicit patient and provider experiences of barriers.