[Extraskeletal mesenchymal chondrosarcoma: rare differential diagnosis of pleural calcifications]

We report on a 78-year-old male patient with unilateral pleural effusion who underwent multiple diagnostic tests including thoracoscopy without establishing a final diagnosis. In the course of time, the patient developed multiple pleural tumors with calcifications. A CT-guided transthoracic biopsy was performed; the specimen revealed histopathological and immunohistochemical evidence for an extraosseous mesenchymal chondrosarcoma. Besides a short review of the literature, the case is discussed as an extremely rare differential diagnosis of pleural calcifications. To the best of our knowledge, this is the first patient in whom the diagnosis of an extraosseous chondrosarcoma, most likely of the pleura, could be established by CT-guided transthoracic biopsy.