Plasmocitoma extramedular. Una raracausa de masa mediastínica

Junio 2017

Caso Clínico 812 Rev Med Chile 2017; 145: 812-815 Plasmocitoma extramedular. Una rara causa de masa mediastínica Javier A. Quilodrán1, Camila Peña2, Ximena Valladares2 Extramedullary mediastinal plasmacytoma. Report of one case 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 marrow aspiration had 1% of plasma cells. Bone x-rays were normal. Computed tomographies of the neck, thorax, abdomen and pelvis ruled out other plasmacytomas. Eight cycles of chemotherapy with thalidomide, melphalan and prednisone were indicated, obtaining complete remission of the tumor. The review of the literature shows that mediastinal extramedullary plasmacytomas are extremely rare. They generally appear in men aged between 50 and 60 years. The treatment of choice is radiotherapy, but given the location in the present case, chemotherapy was considered the best option. Recurrence is approximately 10 to 30% and 10% of patients progress to myeloma, thus requiring close monitoring. (Rev Med Chile 2017; 145: 812-815) Key words: Mediastinal neoplasms; Plasma cells; Plasmacytoma. 1Becado Medicina Interna. Hospital del Salvador. Facultad de Medicina Oriente. Universidad de Chile. Santiago, Chile. 2Sección de Hematología, Servicio de Medicina. Hospital del Salvador. Santiago, Chile. Recibido el 10 de julio de 2016, aceptado el 7 de junio de 2017. Sin apoyo financiero. Correspondencia a: Javier Quilodrán Peredo Av. Salvador 364, Providencia. Santiago, Chile. quiloper@hotmail.com Los plasmocitomas extramedulares (PEM) son una neoplasia de células plasmáticas muy infrecuente, que consiste en una infiltración de células plasmáticas de origen monoclonal, sin compromiso de médula ósea ni otras características sistémicas de mieloma múltiple. Los PEM representan cerca del 3% de todas las neoplasias de células plasmáticas1. Aproximadamente el 80-90% de los casos comprometen el tracto aéreo-digestivo superior2,3. Por lo general, son neoplasias altamente radiosensibles4. Presentan una probabilidad de progresión a mieloma múltiple entre 11 a 30%1. Se presenta el caso de un paciente con un PEM mediastínico que obligó a un enfoque diagnóstico y terapéutico especial para el caso. Caso clínico Paciente sexo masculino, de 70 años de edad. Consulta por disnea y tos no productiva de dos meses de evolución. Estudio con radiografía de tórax evidenció ensanchamiento mediastínico.


Junio 2017
To see the actual publication please follow the link above