Comprehensive analysis of outcomes of patients with colorectal cancer in a racially diverse cohort.

Abstract

3625 Background: Disparate outcomes have been reported among patients with colorectal cancer (CRC) as those with Medicare or Medicaid insurance and those of Native Hawaiian ancestry experience inferior survival. However, many CRC studies addressing Native Hawaiians and other Pacific Islanders and insurance status have not adjusted for a comprehensive range of confounding variables. In this study, we perform a comprehensive analysis of CRC outcomes adjusted for clinicopathological and socioeconomic factors. Methods: Data were abstracted for patients diagnosed with colorectal cancer between 2000 and 2022 in Hawaii. Overall survival of Asians, Whites, and Native Hawaiian or Other Pacific Islanders (NHOPI) was assessed using Cox proportional hazards regression models adjusting for clinical, pathological, and sociodemographic factors. Results: A total of 3275 patients were included in the final analysis. NHOPI were more likely to be younger (p<0.001), had a higher proportion of stable microsatellite status tumors(p=0.049) and were more likely to have Medicaid insurance or be uninsured(p<0.001) compared to Whites and Asians. NHOPI patients more often had high grade cancers compared to White and Asian groups. Medicaid or no insurance was associated with significantly higher mortality compared to private insurance in both univariate(HR: 1.373, 95% CI: 1.202–1.568, p < 0.001) and multivariate analysis(HR: 1.505, 95% CI: 1.309–1.729, p < 0.001). However, while Medicare showed higher mortality in univariate analysis(HR: 1.409, 95% CI: 1.245–1.594, p < 0.001), this association normalized after adjustment(HR: 1.088, 95% CI: 0.958–1.237, p = 0.195) (Table). NHOPI had significantly higher mortality compared to Whites after adjustment for variables(HR: 1.293, 95% CI: 1.107–1.510, p = 0.001). Interestingly, rectal tumors demonstrated higher mortality compared to right-sided tumors(HR: 1.318, 95% CI: 1.156–1.503, p < 0.001), while left-sided tumors showed no significant difference (Table). Conclusions: This study of a racially diverse population that NHOPI patients with CRC had significantly worse mortality compared to Whites after adjusting for clinicopathological and socioeconomic variables. We did not identify a significant association between Medicare insurance and increased mortality. Having Medicaid or being uninsured was significantly associated with worse survival outcomes, emphasizing the critical impact of healthcare access on survival. Univariate and multivariate analysis. Univariate analysisHazard ratio (95% CI), p-value Multivariate analysis Hazard ratio (95% CI), p-value Private insurance Medicaid and Uninsured 1.373 (1.202 - 1.568), <0.001 1.505 (1.309 - 1.729), <0.001 Medicare 1.409 (1.245 - 1.594), <0.001 1.088 (0.958 - 1.237), 0.195 White Asian 0.947 (0.844 - 1.063), 0.354 0.908 (0.808 - 1.02), 0.103 NHOPI 1.143 (0.982 - 1.33), 0.084 1.293 (1.107-1.51), 0.001 Age at diagnosis 1.032 (1.028 - 1.036), <0.001 1.044 (1.039 - 1.048), <0.001 Grade 1&2 Grade 3&4 1.786 (1.586 - 2.012), <0.001 1.485 (1.313 - 1.681), <0.001 Stage 1 Stage 2 1.466 (1.249 - 1.722), <0.001 1.401 (1.192 - 1.647), <0.001 Stage 3 1.644 (1.41 - 1.918), <0.001 1.64 (1.403 - 1.916), <0.001 Stage 4 6.943 (5.898 - 8.173), <0.001 7.681 (6.495 - 9.082), <0.001 Unknown Stage 3.063 (2.525 - 3.714), <0.001 2.99 (2.455 - 3.641), <0.001 Female 0.853 (0.775 - 0.939), 0.001 0.844 (0.765 - 0.931), <0.001 MSI Stable MSI Unstable 1.146 (0.808 - 1.626), 0.444 1.015 (0.71 - 1.449), 0.936 Unknown MSI 1.197 (1.055 - 1.357), 0.005 1.142 (1.003 - 1.3), 0.044 Right sided Left sided 0.899 (0.802 - 1.007), 0.066 1.081 (0.961 - 1.216), 0.197 Rectal 1.016 (0.9 - 1.147), 0.797 1.318 (1.156 - 1.503), <0.001 Time to treatment <31 days Time to treatment >31 days 0.674 (0.593 - 0.766), <0.001 1.064 (0.957 - 1.183), 0.09