The epidemiology of osteosarcoma and comparison of prognostic factors on histologi cal subtypes

Introduction: Osteosarcoma is the most common primary malignant bone tumor in adolescents. Etiology is still unknown. Successful treatment is related to early diagnosis and treatment. So we were working on epidemiology of osteosarcoma and prognostic factors which are very important for diagnosis and predicting of outcomes. Materials and Methods: Epidemiology for 6844 patients with osteosarcoma from the National Cancer Institute's population-based Surveillance, Epidemiology, and End Results (SEER) Program between 1975 and 2016 were investigated by age, race, sex, marital status, histologic subtype, stage, and anatomic site. On histological subtypes, we investigated prognostic factors comparatively. Results: Osteosarcoma was found to be the most common in the 0-25 age group. More common in males than in females. The ratio of singles was found to be higher than the married ones. The most common histological subtype after osteosarcoma NOS (unclassified) was chondroblastic osteosarcoma. The most common anatomic localization was long bones of lower extremity. The survival rate of parosteal and periosteal osteosarcoma was found to be the best and osteosarcoma with paget's disease was the worst. In all histological subtypes, good prognostic facrtors are young age, female, single, primary cancer, low-grade, cancer on the head and extremities, and the surgical treatment similarly. Secondary osteosarcoma, high grade, cancer on pelvis and spine, untreated surgically were found to be poor prognostic indicators.