Plasmacytoma as a cause of obstructive sleep apnea.

Solitary extramedullary plasmacytomas are uncommon neoplasms. They occur most frequently in the upper aerodigestive tract and account for 4% of the nonepithelial tumors in this site. The evolution of a plasmacytoma is unsteady and symptoms at presentation have included dystonia, dysphagia, oral pain, cough, and dyspnea on exertion. Plasmacytoma of the upper aerodigestive tract has not been previously reported as a cause of obstructive sleep apnea.