Ethnic Disparities in Gastric Cancer Presentation and Screening Practice in the United States: An Analysis of 1997–2010 SEER-Medicare Data

Describe differences in Helicobacter pylori (H. pylori) screening among a Surveillance, Epidemiology and End Results (SEER)-Medicare elderly population by ethnicity, place of birth, and gastric cancer (GC)-related conditions, as chronic infection with H. pylori is the strongest risk factor for distal GC. Methods: We used the National Cancer Institute's population-based SEER-Medicare cancer database for GC (1997–2010). We extracted demographic, location and disease staging information from the SEER data file, Patient Entitlement and Diagnosis Summary File. We obtained information on frequencies of various GC-related conditions (e.g., peptic ulcer, gastric ulcer, gastritis) and screening (H. pylori testing and endoscopy) from inpatient hospital and physician/outpatient services claims. Results: Data from 34,730 subjects were analyzed. The majority of Asian American/Pacific Islanders (AAPIs), 65.1%, were foreign-born, while majority of Non-Hispanic Whites (NHW), Hispanics and Blacks were US-born (88.7%, 51.3%, and 96.9%, respectively). NHWs were oldest at diagnosis (74.7 y.); Hispanic and Black cases were the youngest (72.4 and 72.9 y., respectively). For NHWs, the most frequently diagnosed GC site was the cardia (36.1%), while for AAPIs, Hispanics and Blacks, the most diagnosed sites were non-cardia (>80%, P < 0.001). Over 55% of NHW, Hispanic and Black cases were diagnosed at regional or distant stage, while 55% of AAPIs were diagnosed at local or regional stage. Over 57% of all cases had a history of GC-related conditions (AAPIs were highest at 64.1%). However, only 11.2% of total cases showed evidence of H. pylori testing. H. pylori testing was more frequent for foreign-born than US-born (2-fold increase in proportions) and AAPIs exhibited the highest proportion of H. pylori testing (22.6% among those with a GC-related condition). Conclusions: Screening for H. pylori was low for all GC cases, despite race/ethnic groups exhibiting conditions for which H. pylori testing is recommended. AAPI GC cases had the highest frequency of H. pylori testing with tumors staged locally or regionally; increased testing could lead to earlier stage of tumor at diagnosis. Future studies should investigate why screening rates are low in patients with GC-related conditions.