Background: Plasmablastic plasmacytoma of the head neck is a very rare entity with an aggressive behavior.
Case Report: We describe a caucasian man with extramedullary plasmacytoma involving the sinonasal cavity, and stress the importance of the histological subtype of plasma cells on overall prognosis.
Conclusions: Our case illustrates the importance of the histological subtype of extramedullary plasmacytoma. The morphology of the plasma cell is a relevant prognostic marker. Immature and plasmablastic plasma cells are associated with a poor prognosis and early systemic involvement.

Keywords: extramedullary plasmacytoma, head and neck carcinoma, radiation therapy