RESUMEN
Extramedullary plasmacytomas are uncommon malignant neoplasms that can occur in any organ. They arise most frequently from the upper aerodigestive tract. Lymph nodes are exceedingly rare sites of extramedullary plasmacytomas. Most extramedullary plasmacytomas of the lymph node arise in the cervical lymph nodes. Here, we report a case of an extramedullary plasmacytoma of the lymph node arising from a cervical lymph node. A 43-year-old male patient was admitted to our hospital and presented with a non-tender mass on the left side of his neck, which had been growing slowly for 1 month. The mass was excised. The pathology showed diffuse infiltration of immature plasma cells that were encapsulated by a layer of lymphoid cells, indicating an extramedullary plasmacytoma. He was treated with local radiation of the left cervical area. As of March 2009, he is doing well and shows no further evidence of the disease.