Introduction: Malignant bone tumors are rare. In a sample of 1000 pediatric tumors diagnosed in our hospital only 4% were primary bone tumors.

Material and Methodology: The authors present a series of Primary Malignant Bone Tumors, in children and adolescents treated in their Department, referred to a period of 14 years (1991–2004). It’s a series of 45 cases, of which 41 were evaluated. There were excluded 3 malignant low-grade osteosarcomas and 1 Askin tumor (thoracic PNET). The authors evaluated 24 Osteosarcomas, 14 Ewing Sarcomas and 3 PNET. The cases correspond to a population of 24 girls and 17 boys. The study correlate survival rate with tumor histological characteristics, size, stage, chemotherapy protocol used, the percentage of necrotic induction after neoadjuvant chemotherapy and type of surgical plane of dissection.

Results: From patients with high-grade osteosarcomas 71,2% are alive and without disease, with a minimum follow-up of 4 years (1 case) and a maximum of 17 years. On the Ewing Sarcomas/PNET the survival rate is 76%, with the same follow-up period.

Discussion and Conclusions: Due to the improvement of imaging techniques a fast diagnostic orientation is possible. The stage evaluation, combined with chemo and radiotherapy advances, as well as the progress of the surgical techniques to preserve limbs, together contribute to a better prognosis of the disease. The high survival rates permit to face this pathology as a chronic disease.