Historical Redlining, Socioeconomic Status, and Rectal Cancer Outcomes at an NAPRC-Accredited Institution

INTRODUCTION: Several social factors, including poverty, race, and geographic location contribute to inequalities in screening rates, incidence, and death rates in rectal cancer patients. Historical redlining graded "hazardous" regions in neighborhoods based on their population's racial composition. Previous work showed worse cancer outcomes in redlined districts and areas of poorer socioeconomic status (SES). The National Accreditation Program for Rectal Cancer (NAPRC) was established in 2017 to enhance uniformity in treatment, and reduce mortality and complication rates in rectal cancer. The study objective was to determine if there is an association between the implementation of NAPRC standards and improved outcome disparities for rectal cancer affected by areas of historical redlining or poorer SES. METHODS: This was a retrospective cohort analysis in an NAPRC-certified institution in patients with rectal adenocarcinoma from 2020 to 2024. Redlining maps were obtained using Home Owners' Loan Corporation maps from ArcGIS, with zip codes labeled as A/B (desirable) and C/D (unfavorable). SES was measured with a median household income of $74,580 to define low and high status. OUTCOME MEASUREMENTS: Adherence with NAPRC standards of care, recurrence rate, survival rate, and 2-y disease free survival (DFS). RESULTS: Median follow-up was 25 mo. High NAPRC adherence was seen: 95% of patients received tumor board presentations, 93.4% timely treatment, 94.5% pretreatment magnetic resonance imaging, and 97.6% staging computed tomography. Overall cancer recurrence rate was 8.6%, mortality 17.7%, and 2-y DFS 87%. For redlined districts (132 patients: 26 favorable, 106 unfavorable), no differences in stage (P = 0.82), adherence, recurrence (11.5% versus 6.6%), or DFS (88.4% versus 87.8%) was seen. By income (242 low, 142 high), no differences were seen in stage (P = 0.26), adherence to protocol, recurrence (7.8% versus 9.8%), or DFS (86.7% versus 87.3%). CONCLUSIONS: In this NAPRC-accredited institution, there were no disparities based on redlining or SES, and this may suggest that uniformity in treatment may help mitigate existing inequalities. Further research with larger populations is recommended to establish and promote NAPRC implementation.