Solitary Spinal Extradural Plasmacytoma: A Case Report and Literature Review

Solitary spinal extradural plasmacytoma (SSEP) is a rare but distinct form of plasma cell disorder. The clinical picture and treatment of SSEP are reviewed using the seven previously reported cases. The three male and four female patients were aged 40–85 years. The location was cervical spine in one patient, cervicothoracic in one, thoracic in two, thoracolumbar in one, lumbar in one, and extensive involvement in one. Progressive paraparesis and sensory disturbance were the predominant symptoms. Neuroimaging showed a compressive extradural mass lesion in the dorsal spinal canal without findings of local bone destructive changes in all cases. Four of five patients who underwent decompressive surgical maneuver and tumor resection showed neurological improvement. Immunoglobulin (IgG) kappa subtype was the most predominant histological type, followed by IgD lambda and IgA kappa subtypes. SSEP should be included in the differential diagnosis of an extradural tumor located in the dorsal spinal canal without associated bony changes. Surgery may be effective for symptomatic relief.