Hispanic/Latino Ethnicity Is an Independent Predictor of Worse Survival for Gastric Cancer in a Multicenter Safety-Net Patient Population

Abstract

Background: Various population-based studies have shown Hispanic/Latino ethnicity is a risk factor for worse survival in patients with gastric cancer linked to disparate access to care. We aimed to address whether Hispanic patients treated within safety-net hospital systems continue to experience this survival deficit compared to non-Hispanic patients.

Methods: We performed a retrospective cohort study comparing survival between Hispanic and non-Hispanic patients diagnosed with gastric adenocarcinoma between January 1, 2016, and December 31, 2020, within Los Angeles County's safety-net hospital system. Gastric cancer-specific survival was compared between the two cohorts using the Kaplan-Meier estimate and Cox proportional-hazards regression model.

Results: In total, 448 patients who received care from five medical centers were included; 348 (77.7%) patients self-identified as Hispanic and 100 (22.3%) as non-Hispanic. Mean follow-up time was 2.0 years (median 0.91 years, IQR, 0.34-2.5 years). Hispanic patients were found to be diagnosed at a younger age (55.6 vs. 60.7 years, P < 0.01), demonstrate higher state area deprivation index (6.4 vs. 5.0, P < 0.01), and present with metastatic disease (59.8% vs. 45%, P = 0.04). After adjusting social and oncologic variables, Hispanic ethnicity remained an independent risk factor for worse survival [HR 1.56, (95% CI, 1.06-2.28); P = 0.02].

Conclusions: Hispanic patients treated within a large, multicenter safety-net hospital system experience worse survival compared to non-Hispanic patients. This suggests ethnic disparities exist within safety-net hospital systems, independent of known clinicopathologic factors.

Impact: Improving outcomes for Hispanic patients with gastric cancer requires future efforts aimed at defining and addressing these unidentified barriers to care. See related In the Spotlight, p. 12.

Figure 1. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) diagram outlining study design.

STROBE diagram. Initial inclusion criteria using ICD coding identified 1143 patients. After manual chart review, 360 patients were excluded for malignant neoplasms other than gastric adenocarcinoma, 62 for adenocarcinoma of the esophagus, and 270 for insufficient records. No patients were younger than age 18 years at time of diagnosis, and none were found to be pregnant. Three additional patients were excluded due to unknown ethnicity. The final study cohort included 448 patients, of which 348 patients identified as Hispanic and 100 as non-Hispanic.

Figure 2. Comparing survival outcomes between Hispanic and non-Hispanic cohorts.

Comparison of survival outcomes. A) GSS for all patients with gastric cancer stratified by ethnicity (Hispanic vs. Non-Hispanic). Hispanic patients demonstrated worse survival. Log-Rank Test, p = 0.0014. GSS for patients with stage I (B), stage II (C), stage III (D), and stage IV (E), stratified by ethnicity. Stage II Hispanic patients demonstrated a statistically worse survival than non-Hispanic patients (log-rank test, p = 0.03).