Cancer
Survival Patterns in Early-Onset Colorectal Cancer Among Rural Residents in the USA Ransome Eke* Ransome Eke Eke Eke Eke Eke Florida State University College of Medicine
Background: Early-onset colorectal cancer (EOCRC), defined as diagnosis before age 50 years, is increasing in the United States. Rural populations face structural barriers to timely diagnosis and cancer care, yet survival patterns among rural adults with EOCRC remain incompletely characterized. We examined overall survival and within-rural heterogeneity among adults with EOCRC in the USA.
Methods: We conducted a population-based cohort study using Surveillance, Epidemiology, and End Results (SEER) data from 2013–2022. Adults aged 20–49 years with a first primary colorectal cancer residing in nonmetropolitan counties at diagnosis were included. Rural isolation was defined by adjacency to metropolitan areas. Overall survival was the primary outcome. Unadjusted survival differences were assessed descriptively, and a multivariable Cox proportional hazards model estimated the adjusted association between rural isolation and mortality.
Results:
The analytic cohort included 8,193 rural EOCRC patients; 46.0% were female. Forty-one percent (n=3,380) resided in nonmetropolitan counties not adjacent to metropolitan areas. Median overall survival was 66 months. Survival was lower among isolated rural residents compared with metro-adjacent rural residents (median 62 vs 69 months), with higher all-cause mortality (44.7% vs 41.6%; χ² p=0.04). In adjusted Cox models controlling for sex, race/ethnicity, tumor site, and year of diagnosis, isolated rural residence was associated with a modest but not statistically significant increase in mortality risk (HR=1.06; 95% CI: 0.97–1.17; p=0.21).
Conclusions: Rural adults with EOCRC in the USA experience substantial mortality, with worse unadjusted survival among those living in more geographically isolated communities. Findings underscore the importance of examining within-rural structural and healthcare access factors, including stage at diagnosis and treatment patterns, to better understand and address EOCRC survival disparities.
