The impact of ethnicity on the presentation and prognosis of patients with gastric adenocarcinoma

Abstract

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. 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. 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. 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.