Solitary plasmacytoma of the thoracolumbar spine: A rare case report with interdisciplinary management using Closing posterior – Opening Anterior wedge osteotomy and radiotherapy

Abstract

Multiple myeloma is a malignant disease usually originating in the bone marrow, although other tissues may be involved. A plasmacytoma is considered to be a solitary form of multiple myeloma. Solitary bone plasmacytoma representing 3% to 7% of myelomas.We present a man 50-year-old with isolated left flank pain that progressed to back pain with acute numbness and tingling in his lower extremities.MRI detected a single malignant osteolytic process of the spine involving T12 with a pathologic fracture leading to segmental kyphosis.There were no abnormalities to be highlighted in the laboratory. Urgent surgery using Closing Posterior – Opening Anterior Wedge osteotomy was conducted.Histopathological examination specimen showed diffuse proliferation of medium to large plasmacytoid cells. The differential diagnosis included NHL, EMP, SPB, MM, and PBL.Based on the radiographic features, Serum protein electrophoresis and bone marrow, MM was ruled out. A diagnostic workup was done with a panel of following IHC markers. Final diagnosis of SPB was made.The patient recovered well. Follow-up X-ray showed the correction of kyphosis after spinal fusion.Solitary plasmacytoma should be included in the differential diagnosis of a solitary lytic lesion.Closing Posterior – Opening Anterior Wedge osteotomy is an effective method to correct post-plasmacytoma kyphosis.

Keywords

• Solitary plasmacytoma
• Wedge osteotomy
• Kyphosis
• Multiple myeloma