S604 Food Insecurity at the Zip Code Level Is Independently Associated With Delayed Colorectal Cancer Diagnosis: A Geospatial Analysis of SEER Data

Introduction: Delayed diagnosis of colorectal cancer (CRC) has a negative influence on prognosis and increases the treatment burden. While socioeconomic disparities are well-established in cancer treatment, the precise significance of local food insecurity—a measure of nutritional and economic deprivation—has not been well examined. This research uses the geographical interconnectedness and SEER cancer registry data to assess the impact of food insecurity on stage at CRC diagnosis. Methods: We conducted a retrospective cohort study using SEER 18 registries (2010-2019) on adult patients (aged ≥18) diagnosed with incident colorectal cancer (ICD-O-3 codes: C18.0-C20.9). Using United States Census data, geographical relationships were found between patient zip codes and USDA-defined food insecurity rates. The primary outcome was a diagnosis of regional or distant stage (vs localized), as defined by SEER Summary Stage. Multivariable logistic regression was used to examine the relationship between food insecurity quartile and late-stage diagnosis after controlling age, gender, race/ethnicity, insurance status, and urban/rural classification. Spatial autocorrelation and hotspot studies were carried out using ArcGIS Pro and SaTScan. Results: Among 221,380 CRC patients with geocoded zip code data, those in the highest quartile of food poverty had a significantly higher risk of late-stage diagnosis (61.2%) than those in the lowest quartile (48.7%) (P < 0.001). After adjustment, residence in a high-food insecurity region was independently associated with higher chances of late-stage CRC diagnosis (aOR: 1.42; 95% CI: 1.36-1.48; P < 0.001). Spatial cluster analysis revealed significant hotspots in the southern states and the Midwest. The correlation was clear across racial and insurance demographics. Conclusion: Food poverty at the zip code level is a strong, independent predictor of delayed colorectal cancer detection in the United States. These results the need to include socioeconomic variables, including food availability, in cancer prevention and early detection efforts.