University of Texas Southwestern Medical Center Dallas, TX
Introduction: Colorectal cancer (CRC) is a leading cause of morbidity and mortality in the U.S. Literature on cancer outcomes in Middle Eastern and North African (MENA) individuals is limited, largely in part because the U.S. Census has not yet recognized this group as a distinct ethnicity from White individuals. To address this gap, we estimated five-year colorectal cancer-specific survival by race and ethnicity, including patients of MENA ethnicity, in a diverse, population-based sample.
Methods: We identified patients diagnosed with CRC (ages 18-79 years) from 2004 – 2017 using the California Cancer Registry (CCR), including patients who were White, Black, Asian, Hispanic, and MENA. Specifically, MENA patients were identified using a validated list of Middle Eastern surnames linked to the CCR. For each racial/ethnic group, we calculated five-year colorectal cancer-specific survival using Kaplan-Meier estimates and performed Cox proportional hazards regression models to examine the association of race/ethnicity and survival, adjusting for age at diagnosis, sex, insurance, SES, marital status, tumor site, stage at diagnosis, and tumor grade/differentiation.
Results: We identified 110,192 patients with CRC, of whom 58,375 (53.0%) were White, 8,383 (7.6%) Black, 15,448 (14.0%) Asian, 23,539 (21.4%) Hispanic, and 2,656 (2.4%) MENA. Survival was lowest in Black (61.0% ± 0.6%) and highest in MENA (73.2% ± 1.0%) patients (Figure 1). Asian (72.2% ± 0.4%) patients had higher survival compared to White (70.0% ± 0.2%) and Hispanic (68.2% ± 0.4%) patients. In adjusted analysis, MENA (aHR 0.83, 95% CI 0.77, 0.91), Asian (aHR 0.88, 95% CI 0.85, 0.91), and Hispanic (aHR 0.94, 95% CI 0.91, 0.97) race/ethnicity were associated with higher survival compared to White race/ethnicity, and Black (aHR 1.16, 95% CI 1.11, 1.21) race/ethnicity was associated with lower survival compared to White race/ethnicity (Table 1).
Discussion: To our knowledge, this study is the first of its kind to report CRC survival in MENA patients in the U.S. We observed higher rates of survival in MENA patients compared to other racial/ethnic groups, even after adjusting for clinical and sociodemographic factors. While higher adherence to the Mediterranean diet, the “healthy immigrant effect”, and increased social support in MENA patients may, in part, explain survival differences, future studies are needed to establish protective factors and ascertain diagnostic and treatment differences in this unique population.
