Low-grade extraskeletal osteosarcoma of the mediastinum: report of a case and review of literature.

Extraskeletal osteosarcoma (ESOS) is a rare soft tissue sarcoma, typically characterized by a bone-producing neoplasm. Low-grade extraskeletal osteosarcoma (LGESOS) is an extremely rare soft tissue tumor, and patients with LGESOS tend to have a better prognosis. Here, we reported a case of LGESOS of the mediastinum with lung metastasis, and describe its clinical, pathological and radiological features, and compared them with those of the reported cases.