Esophageal cancer (EC) is the 8th most common cancer and the 6th most common cause of death from cancer worldwide. Golestan province located in Northern Iran has been known as a high-risk area for esophageal squamous cell carcinoma (ESCC). Recent reports suggest an increasing rate of esophageal adenocarcinoma (EAC) in this region as well. Designing and implementing of screening programs may be effective for controlling these cancers. The investigators aim to develop a screening program for esophageal cancer in this region. The pilot phase of this project, the Golestan EC Screening Program (GESP), was conducted during 2011 and 2012 among 300 asymptomatic participants of Golestan Cohort Study (GCS), which is a prospective population-based cohort of 50,045 individuals, aged 40-75 years at baseline, in the eastern half of Golestan Province, Iran. The initial results of the GESP project showed a low participation rate for endoscopic screening. In other words, endoscopic ESCC screening was not feasible in our population, suggesting the need for a non-endoscopic screening method. Further results of the GESP project suggested that capsule sponge cytology is a feasible and valid primary method for ESCC screening in this region. Because of the promising findings of the GESP project, it has been decided to start the main phase of the EC screening program, called the "Non-endoscopic EC Screening Program in Northern Iran (NESP)". The aim of this study is to assess the effects of implementation of a non-endoscopic EC screening program on outcomes of interest in an asymptomatic high-risk population in Golestan Province, Iran.