Epidemiology of Esophagus cancer in Ardabil province, a report of population based cancer registry in northwest Iran

Introduction: Esophageal cancer is the 8th most common malignancy and 6th most common cause of cancer death worldwide. Previous studies have shown that Esophagus cancer is the second cancer in male and female in Ardabil province. We provide an update report of Ardabil population based cancer registry to obtain the geographic pattern of Esophagus cancer occurrence in Ardabil province. Aims & Methods: Data on all newly diagnosed Esophagus cancer cases between 2004 and 2006 were actively collected. Age standard incidence rate (ASR) was calculated for each 9 districts of Ardabil province and to provide a comparison between them standard rate ratio calculated for each district. Results:During the period of study 608 new cases of esophagus cancer were registered. the age standardized incidence rate (ASR) of esophagus cancer was 19.5 in men and 19.7 in women per 100,000 person-years. The most common morphology in our cases was squamous cell carcinoma (74.7%) and esophagus adenocarcinoma consisted of 16.1% of all cases. In 33.9% of cases the origin of tumor was in middle third of esophagus and the lower third was consisting of 32.6% of cases that was significantly more common in men whereas in middle third of esophagus the risk of women was higher than men. the incidence of esophagus cancer was significantly higher in northern parts of the province and the highest rate (26.7/100,000) was related to Meshkinshahr that is a district near to the silent volcano of Sabalan. Conclusion:Esophagus cancer is the second common cancer in Ardabil and its incidence has been slightly increased in women since first official report in 2003. High incidence of esophagus cancer in the northern parts of province mandates further investigations of specific environmental and host factors