Clinical and Prognostic Characteristics in Childhood Osteosarcoma: A Single-Center Experience in Türkiye.

In our study, we aimed to share the clinical experiences of our center regarding osteosarcoma cases, the most common primary malignant bone tumor in children and adolescents. With approval from the Clinical Research Ethics Committee of our center, the data of 59 pediatric patients who were followed up in our center with the diagnosis of osteosarcoma between 2007 and 2021 were evaluated retrospectively. The mean time between the onset of symptoms and diagnosis was 3 months. Although not statistically significant, patients with a diagnostic delay of 3 months or less had a higher rate of recurrence and mortality. 59.3% of patients had metastatic disease, and the presence of metastases was associated with higher rates of recurrence and mortality. Significant number of patients had multiple surgical operations. Amputation as the first operation and the need for multiple surgeries were associated with higher mortality. Pathologically poor response to chemotherapy is associated with mortality. 42.4% of patients died, and the 5-year overall and disease-free survival rates were 47.5% and 30.5%, respectively. Survival rates were highest in non-metastatic and non-relapsed patients, and lowest in metastatic patients and patients with poor response to chemotherapy. Renal problems and cardiotoxicity were most frequently treatment-related complications. Significant improvements have been achieved in the survival and quality of life in osteosarcoma cases compared to previous years; however, there is still a long way to go, and more multicenter and multidisciplinary studies are needed on osteosarcoma.