The impact of ethnicity on the presentation and prognosis of patients with gastric adenocarcinoma. Results from the National Cancer Data Base

Abstract

Background: Regional-based studies have indicated that ethnicity is associated with presentation and outcome in patients with gastric adenocarcinoma. To validate this observation in a large cohort, the authors of this report used the National Cancer Data Base (NCDB) to determine whether self-reported ethnicity influences presentation and survival in this patient population.

Methods: Patient demographics, tumor-related features, and treatment-related features were analyzed by ethnicity. Univariate analyses were performed using the chi-square test. Overall median and relative survival rates were examined by using the Kaplan-Meier method. Cox proportional-hazards models were used to identify the predictors of survival outcomes.

Results: Between 1995 and 2002, 81,095 cases of gastric adenocarcinoma were entered into the NCDB. There were 57,943 white patients (71.5%), 11,094 African-American patients (13.7%), 5665 Hispanic patients (7%), 4736 Asian/Pacific Islander (API) patients (5.8%), and 1657 patients of other ethnicities (2%). Significant differences were observed according to ethnicity among the variables that were compared (all P < .01). In patients with stage I and II disease, the 5-year relative survival rates for APIs (stage I, 77.2%; stage II, 48%) were more favorable than for whites (stage I, 58.7%; stage II, 32.8%), African Americans (stage I, 55.9%; stage II, 37.9%), and Hispanics (stage I, 60.8%; stage II, 39.3%). The overall median survival of APIs was more favorable than that of others (P < .01). Predictors of a better outcome were Asian race, female sex, younger age, earlier stage, lower grade, distal tumors, multimodality treatment, and care at a teaching hospital.

Conclusions: Ethnicity was associated with differences in presentation and outcome of patients with gastric adenocarcinoma. APIs had a more favorable outcome than patients of other ethnicities. Further studies should target underlying biologic and socioeconomic factors to explain these differences.