Extramedullary mediastinal plasmacytoma. Report of one case Plasmocitoma extramedular. Una rara causa de masa mediastínica

Abstract

© 2017, Sociedad Medica de Santiago. All rights reserved. Solitary extramedullary plasmacytomas represent 3% of plasma cell neoplasms. Their most common locations are the upper gastrointestinal and respiratory tract. We report a 70-year-old male presenting with progressive dyspnea and cough. A chest radiography showed widened mediastinum. Chest computed tomography showed a mediastinal mass. A bronchoscopy showed an extrinsic compression and complete occlusion of the primary bronchus. A self-expandable prosthesis was installed in left bronchus. A population of plasmacytoid cells was evidenced in the mass biopsy. Immunohistochemistry revealed CD20+ and CD138+. These tumor cells stained positively for lambda light chains, but negatively for kappa chains. Therefore an extramedullary plasmacytoma was diagnosed. A multiple myeloma was discarded with a normal blood count, serum calcium and creatinine levels. Serum protein electrophoresis had a monoclonal spike, serum IgG was 1963 mg/dl. Bone