Primary lymph node Plasmacytoma: Presenting as a solitary neck mass

Abstract

Introduction: Primary plasmacytoma of lymph node is a rare neoplasm. Primary lymph node plasmacytoma represents 2% of all extramedullary plasmacytomas, and only 0.08% of all plasma cell malignant neoplasms. There have been fewer than 20 reported cases worldwide.
Case Report: We hereby report a case of primary lymph node plasmacytoma (PLNP) in a 41 year old man, who presented with a solitary subcutaneous nodule on lateral aspect of his neck, which turned out to be a primary plasmacytoma of the lymph node on histopathological examination. No evidence of the systemic involvement of plasma cell dyscrasia was discovered and thus, the diagnosis of primary lymph node plasmacytoma (PLNP) was made.
Discussion: Plasmacytoma involving lymph node is a rare entity and can occur as a manifestation of regional lymph node involvement in extramedullary plasmacytoma or even more rarely as a primary lymph node plasmacytomas (PLNPs), a complete clinical, radiological and laboratory work up needs to be done to rule out metastatic multiple myeloma and metastatic upper respiratory tract plasmacytomas.
Conclusion: Primary lymph node plasmacytomas (PLNPs) are rare malignant neoplasms representing 0.08% of all plasma cell malignant neoplasms. A diagnosis of plasmacytoma should prompt further clinical, biochemical and radiologic evaluation to determine whether the lesion is purely solitary or a localized presentation of multiple myeloma.