Spontaneous regression of lung metastasis from osteosarcoma: a case report.

: A case of spontaneous regression of a pulmonary metastasis from high-grade osteosarcoma is reported. The metastasis developed 5 years after chemotherapy and amputation for a distal femur osteosarcoma. The sarcomatous nature of the lesion was histologically confirmed. No treatment was attempted owing to the patient's refusal. The patient was followed up every 3 months and a spontaneous regression of the lesion was documented. Seven years after the diagnosis of lung metastases, no pulmonary nodules or other signs of relapse are present.