Esophageal cancer is the second most common malignancy in Iranian men; it is the third in women. It is killing about 5800 Iranians each year. Squamous cell carcinoma (SCC) is presently the most common type of esophageal cancer accounting for about 90% of all esophageal cancers in Iran. Recent studies in Iran have shown that there is a gradual increase in the incidence of adenocarcinoma of the distal esophagus along with gastric cardia adenocarcinoma. Thirty-five years ago, the age-adjusted incidence rate (ASR) of SCC of esophagus in Gonbad city, Golestan province, Northeast of Iran (>100 per 105 people per year), was found to be one of the highest rates for any single cancer ever reported in the world. Recent studies have shown that the incidence of SCC in Gonbad has declined to less than half of what it was in the past. This decline in the incidence of esophageal SCC is in parallel with improvement in socioeconomic status of people living in this region. According to the recent cancer registry data in Iran, there is still an obvious intra-country variability between the incidence of esophageal cancer in South with an ASR of 3 for men and 2 for women in Kerman and 43 and 36, respectively, in northeastern province of Golestan. The reasons for this very high rate of SCC in northeastern Iran have been the subject of several studies during the last 35 years. According to the results of these studies, the suspected risk factors include low intake of fruits and vegetables, drinking hot tea, consumption of opium products and tobacco, H.pylori infection in stomach, using unhealthy drinking water from cistern and genetic susceptibility. The main suspected mutagens are polycyclic aromatic hydrocarbons (PAH) and N-Nitroso compounds. In order to embark on a primary and secondary prevention of this fatal cancer further prospective studies are presently going on in the northeastern Iran. Golestan cohort study of esophageal cancer with enrollment of 50,000 subjects is now in its follow-up phase. We expect simple and feasible evidence based preventive strategies to be implemented in future from the results of these studies.

Background and purpose: Northern Iran has a high incidence for squamous cell carcinoma (SCC) of esophagus, therefore, studying esophageal SCC in different regions of Iran could prepare data for evidence-based and cost effective programs. This study aimed to evaluate esophageal carcinoma in Babol, Northern Iran during 8 years.Materials and methods: This cross-sectional study was conducted in all patients underwent upper endoscopy during 2005-2013 in Babol Shahid Beheshti Hospital. Demographic, endoscopic and pathologic features were analyzed in SPSS V16 and P<0.05 was declared as significant.Results: A total of 8963 patients underwent endoscopy of whom 148 (1.65%) were diagnosed with esophageal carcinoma, including 92 male (61.75%) and 56 female (37.8%). The patients’ mean age was 71±11.6 years (ranging from 38 to 91 years of age). Ten patients (14.8%) and 138 patients (85.2%) were diagnosed with esophageal adenocarcinoma and SCC, respectively. Locations of tumors were determined in upper (31.6%), middle (19.6%), and lower (43%) parts of esophagus.Conclusion: Dysphagia was the most common symptom and lower part of esophagus was the most common site for carcinoma. In this study, there was no gender significance in the incidence of esophageal carcinoma and the number of male and female patients were almost similar. Also, there was no correlation between smoking and opium and esophageal carcinoma which should be investigated in further studies.

Background and purpose: The northern regions of Iran have a high incidence of esophageal cancer. This study was conducted with the aim of epidemiological investigation of esophageal cancer patients in the population covered by Mazandaran University of Medical Sciences. Materials and methods: In this cross-sectional descriptive study, the records of 170 patients over 18 years of age who were referred to Tuba Oncology Clinic (affiliated with Mazandaran University of Medical Sciences) between 2014 and 2016 were reviewed. All relevant information, including age, sex, occupation, marital status, level of education, clinical and pathological findings of patients were collected and analyzed in SPSS V22 using Chi-square and Fisher’, s exact test. Results: The mean age of patients with esophageal cancer was 68. 2±, 12 years. The disease was more frequent in patients aged 70-79 years old. There were 53. 5% male patients and 94. 1% of patients had dysphagia. The frequency of squamous cell carcinoma (SCC) was found to increase by aging. The most and least metastatic segments were middle and upper parts of the esophagus, respectively. Conclusion: Esophageal cancer is common in old age and age is probably the most important factor in developing the disease.

Esophageal cancer (EC) is one of the deadliest malignancies worldwide. Esophageal squamous cell carcinoma (ESCC) constitutes the most common type of EC in Asian countries. Despite advanced surgical techniques, 5-year survival of the affected patients is very low. Therefore, identification of genetic factors and cellular regulatory pathways, including microRNAs (miRNAs), in esophageal carcinogenesis is necessary for early detection. MiRNAs are a class of small non-coding RNA about 18-24 nucleotides in length that negatively regulate gene expression. Deregulation of miRNAs was shown to have a crucial role in the pathways underlying tumorigenesis and tumor progression. Evidence indicates that aberrant expression pattern of miR-100 is associated with pathogenesis of ESCC. The function and expression pattern of miR-100 in ESCC are controversial and its effects in tumor progression has not been fully elucidated. A better understanding of molecular procedures mediated by miR-100 in carcinogenesis, may lead to the opportunity of exploring potential miR-100 based therapeutic applications. In this review, we provide an overview of miR-100, including its important regulation pathways and target genes involved in the development of cancers, emphasizing on its potential role in ESCC.