Solitary plasmacytoma in the cerebellopontine angle.

A case of solitary plasmacytoma of the skull base growing into the cerebellopontine angle is reported. Myeloma protein of the lambda type light chain was identified in the patient's cerebrospinal fluid. The difficulty in differentiating solitary plasmacytomas of the skull base from other tumors in this location, such as chordoma and meningioma, is discussed.