Abstract
Calcifying fibrous tumors are rare lesions that occur throughout the body. A 35-year-old man presented with exertional dyspnea. Computed tomography showed a polypoid mass abutting pericardium, diaphragm, and left chest wall, and a pleural-based lesion adjacent to T12. Thoracoscopy revealed a large mass with diaphragmatic stalk, two pleural-based nodules, and four diaphragmatic nodules. Pathologic analysis of resected lesions showed calcifying fibrous tumors. Three lesions contained heterogenous mutations associated with this tumor type. The patient is disease free 1 year later. Calcifying fibrous tumors should be recognized as rare multifocal pleural and diaphragmatic-based tumors. Complete resection leads to excellent survival for patients with this uncommon disease.