Multiple calcifying fibrous tumors of the pleura

Calcifying fibrous tumor (CFT) is a rare lesion characterized histologically by hypocellular hyalinized collagenous tissue with psammomatous and/or dystrophic calcifications and patchy lymphoplasmacytic infiltrates. CFT usually occurs in the somatic soft tissue of children and young adults but is rarely found in the pleura. We describe here an unusual case of multiple small CFTs in the right mediastinal pleura of a 54-year-old man who had a history of renal cell carcinoma. Suspecting pulmonary and pleural metastases, we performed wedge resection of the right middle lobe and local excision of two nodules in the right pleura. Light microscopy revealed metastatic lesions of renal cell carcinoma in the resected wedge. The pleural nodules were well circumscribed and composed of hypocellular, dense, hyalinized, collagenous tissue with scant lymphoplasmacytic infiltration and characteristic psammoma bodies. Immunohistochemical staining revealed that most spindle cells were positive for vimentin, CD34 and factor XIIIa, and negative for epithelial membrane antigen, keratin, smooth-muscle actin, desmin, S-100 protein and anaplastic lymphoma kinase. We made a histological diagnosis of CFT of the pleura, and the patient remains well 6 months after the wedge resection.