Descriptive Epidemiology of Malignant primary osteosarcoma in Tunisia 1980-2016

Abstract Background Osteosarcoma is a rare malignant tumor of the mesenchymal tissue that accounts for 5% of all malignant tumors in children and teenager. The purpose of our study was to describe epidemiological and evolutionary characteristics of osteosarcoma in Tunisia. Methods It’s a retrospective study performed in the Oncology Department of Salah Azaiez Institute from January 1980 to December 2016. We analyzed records of 200 cases of patients with primary high grade osteosarcoma. Results The mean incidence was 6 cases per year. The mean age at the time of diagnosis was 19 years with a slight male predominance (55%). The distribution had a single peak during adolescence and a plateau during adulthood. The average consultation period was 3.4 months. The most common reasons for consultation were pain (82%), followed by swelling (74%), trauma (10%), fracture (6.5%), and functional impairment (5.5%).  Mean tumor size was 11 cm. Preferred site was long bones in young patients and flat bones in elderly ones. Common osteosarcoma was the most frequent (85%). Overall survival and progression free survival at 5 years were respectively 78% and 90.5%. .  Conclusion In summary, this study is a large national population-based incidence report of osteosarcoma in Tunisia.