P-0074 - Increasing Incidence of Gastric Adenocarcinoma in Young Hispanic Residents of the United States

Date 28 June 2014
Event World GI 2014
Session Poster Session
Topics Cancer in Young Adults
Gastric Cancer
Cancer Aetiology, Epidemiology, Prevention
Presenter Rebecca Nelson
Citation Annals of Oncology (2014) 25 (suppl_2): ii14-ii104. 10.1093/annonc/mdu165
Authors R. Nelson1, S. Merchant1, R. Kauffmann1, J. Hamner1, J. Kim2
  • 1City of Hope, Duarte/US
  • 2City of Hope, Los Angeles/US

Abstract

Introduction

The average age at diagnosis of gastric adenocarcinoma is generally ≥60 years. We have observed an increased number of young patients with gastric adenocarcinoma. Our objective was to determine whether the incidence of gastric adenocarcinoma in younger patients has changed over the past severaldecades.

Methods

The National Cancer Institute's Surveillance Epidemiology and End Results (SEER) cancer registry was queried to assess a broad spectrum of US patients with gastric adenocarcinoma. Patients who were 20-49 years of age were identified and grouped into 4 major racial/ethnic groups [(whites, blacks, Hispanics, and Asian/Pacific Islanders (APIs)]. Population-based age-adjusted incidence rates were measured from 1992-2010. Tumor location and stage of disease were also examined.

Results

Assessment of the 4 patient groups (180,000 patients) revealed a significant increase in age-adjusted incidence of gastric adenocarcinoma for young Hispanic patients. In contrast, there was a decreased incidence observed in whites, blacks and APIs. The average annual age-adjusted increase from 1992 to 2010 in young Hispanics was 1.9% per year (95% CI 0.8 to 3.0). The average annual decrease in whites, blacks and APIs was -1.4% (-3.0 to 0.3), -2.3% (-4.1 to -0.4) and -3.0% (-4.0 to -1.8), respectively. Focused analysis of older Hispanic patients (≥50 years) demonstrated decreased incidence of gastric adenocarcinoma during the same study period. In young Hispanic patients the increased rate of gastric cancers primarily involved the whole stomach, whereas rates of both proximal and distal tumors decreased. There was an expected increase in metastatic tumors for young Hispanic patients.

Conclusion

Our investigations reveal an alarming increase in the incidence of gastric adenocarcinoma in young Hispanics in the US. Given that the overall incidence rates continue to trend downward for all other racial/ethnic and age groups, the etiology of the increase in young Hispanic patients is unclear and merits further investigation.