Incidence trend of esophageal squamous cell carcinoma: an analysis of Surveillance Epidemiology, and End Results (SEER) database.

Abstract

Esophageal cancer is the sixth leading cause of cancer deaths worldwide [1]. In the USA, an estimated 18,170 new cases of esophageal cancer will be detected in the year 2014 [2]. Although prior studies have shown a decline in the incidence of esophageal squamous cell carcinoma (SCC) in the USA and worldwide [3–5], it is unknown if this continues to be true in recent years. We utilized Surveillance, Epidemiology, and End Results (SEER) 18 database to determine the trend in the incidence of esophageal SCC in the USA between 2000 and 2011. SEER is a program of the National Cancer Institute that provides cancer incidence and survival data from population-based cancer registries covering 28 % of the US population. Eligible patients were identified using SEER histology codes 8050-8089. Age-adjusted rates were plotted by time period using a logarithmic scale for the ordinate. Genderand race-specific trends were also calculated. Data analysis was done using SEER*Stat 8.1.5, and trend analysis was done using Jointpoint regression program 4.1. A total of 344,408 cases of esophageal squamous cell carcinoma were identified during the study period. The study population included 57.9 % males, 82.1 % whites, and 12.1 % African-Americans (AA). The age-adjusted incidence rate steadily decreased from 40.2/100,000 in 2000 to 34.0/100,000 in 2011 (annual percentage change [APC] -1.1, p \ 0.05). The decline in incidence was observed in both sexes and all races (Fig. 1); however, the decline was most prominent in AA males (APC -3.2, p \ 0.05) (Fig. 1a). Our study demonstrates a continual decline in the incidence of esophageal SCC between 2000 and 2011. Prior studies by Trivers et al. [5] and Cook et al. [6] have shown a steady reduction in the incidence of esophageal SCC in the USA prior to 2005. This reduction has been attributed largely to a decreased prevalence of smoking [7]. Although the decline in our study was observed in both genders and all races, it was most prominent in AA males. African-Americans, compared to whites, have higher mortality rate from esophageal cancer; hence, a decrease in the incidence of esophageal SCC in AA is encouraging [2]. This is likely the result of a rapid decline in smoking rates in this population, which highlights the importance of efforts toward risk reduction. It is estimated that between the mid-1970s to early 1990s, the drop in smoking rates among AA youths was twice as much as that among whites [8, 9]. This decline has continued in the recent years as well [10]. SEER is a de-identified database; hence, the accuracy of coding cannot be verified. We were not able to compare the prevalence of risk factors for esophageal SCC among different subgroups that may have accounted for the observed racial differences.