The Features of Esophageal Cancer in Ardabil Province:Report of a Population-based Cancer Registry in Northwest Iran

Abstract

Background: Evidence shows that the mortality rate of esophageal cancer (EC) in Ardabil Province is among the highest worldwide. Studies on the epidemiological profile of EC in Ardabil are scarce. We aim to study the characteristics of EC in Ardabil using data from the recently established Ardabil Cancer Registry (ACR).

Materials and Methods: This study has been accomplished based on data collected in ACR between 2004 and 2006. Cases reported to ACR were coded based on the third edition of the International Classification of Diseases for Oncology (ICD-O III). The age-standardized incidence rates (ASR) and the standard rate ratio (SRR) have been calculated for each district in Ardabil Province.

Results : A total of 549 new cases of EC were registered within ACR during the study period. The ASR was 19.5 for men and 19.7 for women per 100,000 person-years. The majority of cases (79.1%) were diagnosed based on pathology. The most common morphology of EC was squamous cell carcinoma (SCC, 73%) followed by adenocarcinoma (17.8%). The ASR was significantly higher in northern districts of the province (p < 0.001); highest in Meshkinshahr (27.2/100,000) and lowest in Nir (7.6/100,000). The male:female ratio approximated one in the northern and above 2.5 in the southern districts.

Conclusion : Our results demonstrate that the increased incidence of EC in Ardabil is mainly due to an increase in the incidence of esophageal adenocarcinoma (ACE) during recent years. The almost equal incidence of EC among men and women, and its geographical pattern across the province indicate the possible role of environmental risk factors, which need further investigations.