Giant osteosarcoma of chest wall requiring resection and pneumonectomy.

We present the case of a 13-year-old girl who had a large swelling in her left breast with a history of weight loss, low-grade fever, and cold sweats. Computed tomography showed a large mass encroaching on the mediastinum and heart, with erosion of the adjacent ribs. Resection of the mass along with a pneumonectomy were performed. Postoperative tests showed no sign of metastases.