Osteosarcoma: Experience at Instituto Especializado de Enfermedades Neoplásicas (1985–2000)

Abstract

9081 Background: Osteosarcoma is a malignant tumor of the bone arising from osteoblastic cells, being more frequent in long bones; this cancer affects usually to teenagers. Mutations on TP53 and rb genes may be present. The aim of this study was to determine the clinical characteristics of Peruvian patients with osteosarcoma. Methods: A retrospective clinical study of 296 patients with diagnosis of osteosarcoma from Instituto Especializado de Enfermedades Neoplásicas (Lima-Perú) treated between 1985 to 2000 was performed. Clinical characteristics as hystologic type, metastasis at diagnosis, and clinical response were evaluated. Disease-free survival to five years was estimated by Kaplan-Meier and survival curves were compared by Longrank test. Results: The median age was 19 years (range 14–77 years), with a median of 19 years; 61.5% of patients (182/296) were male; femur was more frequent site of involvement (49%\(\frac{145}{296}\)), followed by tibia (22%\(\frac{66}{296}\)). Conventional osteosarcoma subtype was more frequent. 30.4% of patients (90/296) had metastasis at diagnosis. Disease-free survival was 26%; 43.9% had progression of disease; was observed a lower rate of overall survival in patients with pulmonary metastasis (35%) than patients without metastasis at diagnosis (52%). Conclusions: Osteosarcoma is usually frequent in young patients and more frequent in male than female; femur is the site of more frequent involvement; the overall survival is related with metastasis at diagnosis. No significant financial relationships to disclose.