S263 Disparities in Survival and Stage at Diagnosis in Ethnic and Racial Minorities Diagnosed With Early Onset Colorectal Cancer

Abstract

Introduction: Although the overall incidence of early onset Colorectal Cancer (eoCRC) is increasing, the incidence remains higher among Black and Hispanic patients than non-Hispanic whites. The aim of this study was to examine racial and ethnic disparities in the stage at diagnosis and survival of patients with eoCRC. Methods: We conducted a retrospective cohort study using the National Cancer Institute’s Surveillance, Epidemiology, and End Results 18 Registries (SEER 18) Program Research Plus database. We included all patients aged <50 years diagnosed with eoCRC from 2000-2017. Selected variables of interest included race/ethnicity, stage at diagnosis, and survival time. Survival analysis was limited to patients diagnosed between 2000-2012 to include minimum 5-year survival data. The study was certified exempt by the University of Washington IRB. Results: 71,651 patients were identified of whom 58.5% were non-Hispanic White (NHW) patients and 41.5% were racial/ethnic minorities. 24,229 patients had localized (stage I-IIc), 26,947 patients had regional (stage IIIa-c), and 17,805 patients had distant (stage IVa/b) eoCRC at diagnosis. Patients from racial/ethnic minorities were significantly more likely to be diagnosed with distant eoCRC compared to NHW patients (Table) (p< 0.01). These differences were greatest for non-Hispanic Black (NHB) patients. Overall as well as stage-specific 1-year and 5-year survival was significantly shorter in racial/ethnic minorities (Figure) (p< 0.01). These differences were again greatest in NHB patients. Conclusion: Significant differences in stage at diagnosis were seen between NHW and racial/ethnic minorities with eoCRC. Significant racial/ethnic differences were also seen in overall median survival and median survival at all stages of diagnosis. For both stage and survival, the greatest differences were seen in NHB patients followed by American Indian/Alaska Native patients. Further study is needed to understand the reason for these disparities.Figure 1.: Kaplan Meier curve depicting overall 5-year survival of patients with eoCRC stratified by race/ethnicity Table 1. - Stage at diagnosis, 1-year and 5 year survival rate of patients diagnosed with eoCRC stratified by race/ethnicity Stage Race/Ethnicity Portion of Racial/Ethnic Cohort 1-year Survival Rate 5-year Survival Rate Overall (n = 48,987) All Races/Ethnicities 100% 89.3% 66.6% Non-Hispanic White 100% 89.8% 68.4% Non-Hispanic Black 100% 85.6% 57.8% Hispanic (all races) 100% 89.3% 66.0% Asian of Pacific Islander 100% 91.0% 67.8% American Indian/Alaska Native 100% 87.4% 61.5% Unknown 100% 98.7% 97.4% Localized (n = 16,510) All Races/Ethnicities 33.7% 98.2% 91.6% Non-Hispanic White 34.3% 98.4% 92.3% Non-Hispanic Black 32.5% 97.1% 87.8% Hispanic (all races) 31.9% 97.9% 90.6% Asian of Pacific Islander 32.4% 99.2% 93.5% American Indian/Alaska Native 31.5% 95.3% 85.8% Unknown 13.7% 99.6% 99.6% Regional (n = 18,706) All Races/Ethnicities 38.2% 95.5% 74.9% Non-Hispanic White 38.8% 95.6% 76.7% Non-Hispanic Black 35.0% 93.8% 66.3% Hispanic (all races) 38.7% 95.7% 74.2% Asian or Pacific Islander 40.5% 96.4% 75.7% American Indian/Alaska Native 36.3% 94.0% 74.1% Unknown 13.7% 100% 96.2% Distant (n = 12,011) All Races/Ethnicities 24.5% 67.6% 19.3% Non-Hispanic White 23.7% 68.1% 20.2% Non-Hispanic Black 28.2% 62.2% 12.2% Hispanic (all races) 25.5% 69.3% 23.1% Asian or Pacific Islander 23.8% 71.2% 19.8% American Indian/Alaska Native 26.9% 68.3% 15.1% Unknown 3.7% 85.5% 64.3% Unstaged (n = 1,760) All Races/Ethnicities 3.6% 87.2% 67.0% Non-Hispanic White 3.2% 87.2% 67.9% Non-Hispanic Black 4.3% 84.7% 60.9% Hispanic (all races) 3.9% 87.4% 63.3% Asian or Pacific Islander 12.4% 86.3% 65.1% American Indian/Alaska Native 5.1% 97.5% 66.7% Unknown 20.3% 97.4% 97.4%