Nazal Kavitede Ekstramedüller Plazmasitoma.

Plasmacytomas are malignant tumors characterized by abnormal monoclonal proliferation of plasma cells. They originate either in the bone (osseous solitary plasmacytoma) or in soft tissues (extramedullary plasmacytoma) and could be either primary or a part of a systemic process during the course of multiple myeloma. [ABSTRACT FROM AUTHOR]