E0166 - Analysis of Colorectal Cancer Survival in Middle Eastern Patients Using the California Cancer Registry

Tuesday, October 25, 2022

3:00 PM – 5:00 PM ET

Location: Crown Ballroom

Has Audio

Presenting Author(s)

Timothy Zaki, MD

University of Texas Southwestern Medical Center
Dallas, TX

Timothy Zaki, MD¹, Argyrios Ziogas, PhD², Jenny Chang, MPH², Hoda Anton-Culver, PhD²
¹University of Texas Southwestern Medical Center, Dallas, TX; ²University of California, Irvine School of Medicine, Irvine, CA

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.

Figure: Five-year colorectal cancer-specific survival (age 18-79 years) using Kaplan-Meier estimates, by race/ethnicity, California Cancer Registry, 2004 – 2017

	Overall Survival				Colorectal Cancer-specific Survival
	Adjusted HR and 95% CI			p-value	Adjusted HR and 95% CI			p-value
Age at diagnosis	1.03	1.03	1.03	< .0001	1.02	1.02	1.02	< .0001
Year of diagnosis	1.02	1.01	1.02	< .0001	1.00	0.99	1.00	0.022
Female	0.84	0.82	0.86	< .0001	0.90	0.88	0.92	< .0001
Race/ethnicity
Middle Eastern/North African	0.80	0.75	0.86	< .0001	0.83	0.77	0.91	< .0001
Non-Hispanic White	Ref				Ref
Non-Hispanic Black	1.13	1.09	1.17	< .0001	1.16	1.11	1.21	< .0001
Hispanic	0.92	0.90	0.95	< .0001	0.94	0.91	0.97	0.0004
Non-Hispanic Asian or Pacific Islander	0.84	0.81	0.86	< .0001	0.88	0.85	0.91	< .0001
Insurance
Managed care	Ref				Ref
Medicare	1.12	1.09	1.14	< .0001	1.05	1.02	1.08	0.0026
Medicaid	1.34	1.30	1.39	< .0001	1.29	1.24	1.34	< .0001
Other	0.91	0.88	0.94	< .0001	0.93	0.89	0.97	0.0005
Not insured or unknown	1.24	1.18	1.30	< .0001	1.30	1.23	1.38	< .0001
Socioeconomic Status (SES)
Lowest SES	1.40	1.36	1.45	< .0001	1.33	1.27	1.38	< .0001
Lower-middle SES	1.33	1.29	1.37	< .0001	1.28	1.23	1.33	< .0001
Middle SES	1.22	1.18	1.26	< .0001	1.20	1.16	1.25	< .0001
Higher-middle SES	1.14	1.11	1.18	< .0001	1.10	1.06	1.14	< .0001
Highest SES	Ref				Ref
Marital status
Single or other	Ref				Ref
Married	0.77	0.76	0.79	< .0001	0.81	0.79	0.83	< .0001
Tumor site
Colon	Ref				Ref
Rectum	1.05	1.03	1.08	< .0001	1.09	1.06	1.12	< .0001
Tumor stage
I	Ref				Ref
II	1.58	1.53	1.64	< .0001	2.70	2.53	2.87	< .0001
III	2.33	2.25	2.41	< .0001	5.41	5.10	5.74	< .0001
IV	11.87	11.48	12.27	< .0001	31.80	30.02	33.68	< .0001
Tumor grade or differentiation
Grade I or well differentiated	Ref				Ref
Grade II or moderately differentiated	1.17	1.12	1.22	< .0001	1.32	1.24	1.39	< .0001
Grade III or poorly differentiated	1.68	1.61	1.76	< .0001	2.06	1.94	2.18	< .0001
Grade IV or undifferentiated/anaplastic	1.84	1.70	1.99	< .0001	2.22	2.02	2.45	< .0001
Grade/differentiation unknown	1.94	1.86	2.04	< .0001	2.20	2.07	2.34	< .0001

Table: Table 1. Adjusted hazard ratios demonstrating association of race/ethnicity and survival (overall and colorectal-specific), California Cancer Registry, 2004 – 2017

Disclosures:

Timothy Zaki indicated no relevant financial relationships.

Argyrios Ziogas indicated no relevant financial relationships.

Jenny Chang indicated no relevant financial relationships.

Hoda Anton-Culver indicated no relevant financial relationships.

Timothy Zaki, MD¹, Argyrios Ziogas, PhD², Jenny Chang, MPH², Hoda Anton-Culver, PhD². E0166 - Analysis of Colorectal Cancer Survival in Middle Eastern Patients Using the California Cancer Registry, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.