Esophageal cancer incidence rates by histological type and overall: Puerto Rico versus the United States Surveillance, Epidemiology, and End Results population, 1992-2005

Objective: The aim of our study was to compare the age-standardized incidence of esophageal cancer (EC) in Puerto Ricans (PRs) with that for non-Hispanic White (NHW), non-Hispanic Black (NHB), and Hispanic (USH), groups in the United States (US) as reported by the Surveillance, Epidemiology, and End Results program for the 1992-2005 period. Methods: We computed the age-standardized and age-specific incidence (per 100,000 individuals) of EC during 1992-2005 using the World Standard Population as reference. The percent changes for age-standardized rates (ASR), from 1992-1996 to 2001-2005, were calculated. The relative risks (RR) and the standardized rate ratios (SRR) were estimated, along with 95% confidence intervals (CIs). Results: The ASR of adenocarcinomas (AC) showed increases for most racial/ethnic groups from 1992-1996 to 2001-2005. All racial/ethnic groups showed ASR reductions for squamous cell carcinomas (SCC). For both sexes, PRs had lower AC incidences than NHW and USH but higher than NHB. For those younger than 80 years of age, PR men showed higher SCC incidences than NHW but lower than NHB (P < 0.05). The incidence of SCC was about two times higher in PR men than USH men (SRR: 2.16; 95% CI = 1.65-2.88). Among women, the RR for SCC increased with age when comparing PRs to groups in the US. Conclusion: Incidence disparities were observed between PRs and other racial/ethnic groups in the US. These differences and trends may reflect lifestyles of each racial/ethnic group. Further studies are warranted to explain these disparities.