Sellar solitary plasmacytoma progressing to multiple myeloma: a case report and literature review.

Sellar plasmacytoma is a rare cause of sellar lesions. Preoperative diagnosis remains a challenge. We present a 34-year-old Chinese woman with a 25-day history of headache and diplopia. A physical examination revealed incomplete left abducens nerve palsy. The initial diagnosis was invasive pituitary adenoma. The patient's condition deteriorated suddenly the day before the arranged operating date, with the hemoglobin level declining from 113 to 70 g/L. The operation was cancelled and further studies confirmed the diagnosis of sellar solitary plasmacytoma that progressed to multiple myeloma. After undergoing radiotherapy, high-dose chemotherapy, and autologous peripheral blood stem cell transplantation, complete remission was achieved on 4 years follow-up. We reviewed the pertinent literature and reached the following conclusions: sellar plasmacytomas with development of multiple myeloma on follow-up more likely happened in men than in women; and if the sellar plasmacytoma does not compress the cranial nerve, transsphenoidal resection should be cautious because the systemic treatment with radiotherapy, chemotherapy, and autologous peripheral blood stem cell transplantation may be more effective with little invasion.