Primary myofibrosarcoma of the lung. A rare case with challenging diagnosis.

Primary myofibrosarcoma (MFS), or myofibroblastic sarcoma of the lung, is a rare tumor. A 47-year-old man with a history of melanoma presented with a central tumor of the left lung. The initial diagnosis was inflammatory myofibroblastic tumor but after extensive pathologic analysis MFS of the lung was confirmed. He underwent left pneumonectomy and died on the 6th postoperative month. This is the second case of primary pulmonary MFS to be reported.