Intrasellar plasmacytoma: an unusual presentation of multiple myeloma

Introduction Plasmacytomas are unusual causes of a sellar mass. Occasionally, they can be misdiagnosed as a nonfunctioning adenoma because of radiological and clinical similarities. Literature review We reviewed the pertinent literature and discuss here in the light of an illustrative case of our own. Discussion A 70-year-old woman presented with a recurrent hypophysial mass. Initial diagnosis of a nonfunctioning pituitary adenoma was later overruled by a repeat biopsy, which showed a plasmacytoma. The tumor stained positively for CD138 and kappa light chain. Further studies confirmed the diagnosis of multiple myeloma. The patient was successfully treated with radiotherapy followed by systemic chemotherapy. Because they have different therapeutic implications, extramedullary plasmacytomas involving pituitary gland should be considered in the differential diagnosis of a nonfunctioning pituitary mass.