Adel Ebrahimpour - Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran - Department of Orthopedic Surgery, Shohadaye Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Mohammadreza Chehrassan - Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran - Department of Orthopedic Surgery, Shohadaye Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Mehrdad Sadighi - Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran - Department of Orthopedic Surgery, Shohadaye Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Mehdi Azizmohammad Looha - Department of Biostatics, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran

Background: The effect of race and ethnicity on some kind of malignant bone tumors including Ewing sarcomahas been proven in different studies. In order to evaluate the latter, national cancer registries may help to increaseunderstanding about potential cancer causes, prevention and control strategies, and apply these findings to controlhealth problems among populations with similar characteristics.Methods: A national population-based cancer registry study based on all patients affected by Ewing Sarcoma wasregistered in the Iran National Cancer Registry (INCR) between 2008 and 2015 was designed. Demographic data ofmicroscopically confirmed cases of bone Ewing sarcoma were registered. Patients with Ewing sarcoma were dividedin groups to describe the primary site of the tumor (including axial or appendicular bones) and analyzed. In order toanalyze the survival rate, randomized selection of the patient through the INCR data-base was performed.Results: A total of 678 cases of malignant Ewing sarcoma of the bone were identified through the INCR. The meanage of Ewing sarcoma in Iran was 21.53 years. Nearly half of patients were observed at the age group of 15-24. Thetotal crude incidence rate of Ewing sarcoma was 1.29 in 1 million. The mean 5 year survival rate was 47%. The Meansurvival rate for study population was 5.53.Conclusion: The crude incidence rate of Ewing sarcoma in Iran is relatively lower with respect to other registries. Themajority of patients are in 15-25 years group and shows affection by Ewing sarcoma in an older age. Socioeconomicfactors had direct influence on survival rate.Level of evidence: IV

Ewing sarcoma, Malignant bone tumors, Sarcoma