title: Extramedullary plasmacytomas presenting as mediastinal masses: clinicopathologic study of two cases preceding the onset of multiple myeloma.
abstract: We present two cases of extramedullary plasmacytoma presenting as a mediastinal mass and preceding the onset of full-blown multiple myeloma. The patients are a 62-year-old woman who presented with progressive dyspnea and left-sided chest pain and a 59-year-old asymptomatic man. In both patients, radiographic studies revealed a posterior and anterior mediastinal mass, respectively. Surgical resection of the tumor was performed in the two cases. The tumors were characterized by a well-circumscribed proliferation of plasma cells surrounded by residual lymph nodal tissue. Immunohistochemical studies on paraffin sections demonstrated lambda light chain restriction. Follow-up in our patients revealed that both of them developed multiple myeloma after 6 months and 2 years, respectively. One patient received treatment with melphalan and prednisone and is currently alive and well without evidence of disease, 2 years after diagnosis. The second patient died 4 years after resection of his tumor with evidence of disease in lumbar spine, skull, and lungs. Extramedullary plasmacytoma presenting as a mediastinal mass may precede the onset of full-blown multiple myeloma; therefore, institution of early systemic therapy in these patients may be of value in preventing further progression of the disease.
authors.affiliation: Department of Pulmonary and Mediastinal Pathology, Armed Forces Institute of Pathology, Washington, DC, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Moran
authors.forename: S
authors.initials: S
authors.lastname: Suster
authors.forename: N F
authors.initials: NF
authors.lastname: Fishback
authors.forename: M N
authors.initials: MN
authors.lastname: Koss
mesh_terms: D002637:Chest Pain / Q000150:complications; D003131:Combined Modality Therapy; D003937:Diagnosis, Differential; D004417:Dyspnea / Q000150:complications; D017809:Fatal Outcome; D005260:Female; D006801:Humans; D007146:Immunoglobulin lambda-Chains / Q000032:analysis; D008297:Male; D008479:Mediastinal Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D008558:Melphalan / Q000627:therapeutic use; D008875:Middle Aged; D009101:Multiple Myeloma / Q000473:pathology*; D010950:Plasma Cells / Q000737:chemistry / Q000473:pathology; D010954:Plasmacytoma / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D011241:Prednisone / Q000627:therapeutic use
chemical_list: D007146:Immunoglobulin lambda-Chains; D008558:Melphalan; D011241:Prednisone