Bone and Soft Tissue Sarcomas

Outcomes OS

• 60-68% of patients with nonmetastatic osteosarcoma of the extremity will survive without recurrence and be cured
• 20% of patients with metastatic disease will be cured
• Therapy with curative intent is possible following relapse: 10-20% of these patients may achieve long term survival

Complications / Late effects of Therapy OS

• Surgical
• Functional outcomes of limb salvage vs. amputation under study
• Chemotherapy
• Anthracycline induced cardiomyopathy
• may arise 15+ years after therapy
• Cis-platinum induced ototoxicity and renal toxicity
• Ifosfamide induced renal tubular dysfunction

Ewing Sarcoma (EWS)

• Represents a family of tumors including
• Ewing sarcoma of bone
• extraosseous Ewing sarcoma and
• peripheral neuroectodermal tumor (PNET) of bone or soft tissue
• 2nd most common bone tumor in children

Pathology EWS

• One of many ‘small round blue cell’ tumors seen in pediatrics
• Thought to be of neural origin, derived from post-ganglionic parasympathetic primordial cells
• tumor cells synthesize acetylcholine transferase

Small, Round, Blue Cell Tumor

• Differential Diagnosis
• Lymphoma/Leukemia
• Rhabdomyosarcoma
• Metastatic Carcinoma
• Neuroblastoma
• PNET/Ewing Sarcoma
• Small Cell Osteosarcoma

• Ewing
• Tumor without differentiation
• PNET
• Tumor with neural differentiation

Incidence EWS

• Occurs most commonly in 2nd decade
• 80% occur between ages 5 and 25
• Most common bone tumor in children < 10 yrs
• ~110 new cases/year < 15 yrs ~200 new cases/year < 20 yrs
• M:F 1.3:1 < 10 yrs 1.6:1 > 10 yrs
• Rare in African-Americans and Asians