Running Title: Improvement of Survival of Esophageal Cancer Patients at Cancer Institute of Iran

Background: Iran is a high-risk area with a poor prognosis for esophageal cancer. We conducted the present study to evaluate the survival rate of esophageal cancer after the introduction of neo-adjuvant chemo-radiation at the Cancer Institute of Iran. Method: We performed a retrospective cohort study and abstracted the data of 421 patients who referred to the Cancer Institute of Iran between 2007 and 2011. Life table and KaplanMeier approaches were applied to estimate 1, 3, and 5-year survival rates and corresponding 95% confidence intervals (CI). Multiple Cox regression model was recruited for investigating the association between 5-year survival rate and prognostic factors. Results: We found that 1, 3, and 5-year survival rates were 66.7%, 28.2, and 20.9%, respectively. The hazard ratio was significantly higher among the patients who has received definitive chemo-radiation therapy (Hazard ratio (HR) = 2.2, 95% CI: 1.1, 4.2), surgery (HR= 2.0 95% CI: 1.0, 3.7), and palliative care (HR= 4.2, 95% CI: 2.1, 1.8) compared to those who received neo-adjuvant chemo-radiation and surgery. We also found that the 5-year survival rate was doubled in the current study conducted between 2007 and 2011 (20.9%) compared to the previous one conducted between 1997 and 2006 (10.0%). Additionally, a considerable improvement was observed in 1 and 3-year survival rate of esophageal cancer at the Cancer Institute of Iran. Conclusion: Following the administration of neo-adjuvant chemo-radiation therapy, the prognosis of esophageal cancer has improved significantly at the Cancer Institute of Iran during the last decade. More data from other cancer centers and provinces of Iran are required.