Introduction: Inflammatory pseudotumor (IPT) is an uncommon and difficult diagnosis of obscure mass that could only be verified upon histological analysis. They are an extremely rare occurrence in the CNS. The current report presents a case of an epidural IPT of the cervical spine in a patient with a history of dermatomyositis.

Methods: A 26-year-old man with a history of dermatomyositis presented with progressive neck pain and stiffness, as well as numbness in his right arm and fingers over the past 6 months. Gadolinium enhanced-MRI revealed a mass in the posterior spinal canal, spanning levels C2 through C6 and most prominent at C3-C4, best visualized with a T1 gadolinium-enhancement MRI. A C3-C4-C5 laminectomy was performed with resection of an epidural mass measuring approximately 5cm x 2cm with subsequent posterior fusion.

Results: Upon histological analysis, the surgical sample was found to be soft tissue fragments with dense chronic inflammatory infiltrate, without evidence of malignancy. Immunohistochemistry showed a diverse collection of polymorphous lymphocytes (CD3, CD20), histiocytes (CD68), reactive fibroblasts (vimentin), and capillary endothelial cells (CD34).

Conclusions: The initial differentials included primarily neoplastic growths, since IPTs are uncommon to the CNS. Currently, IPT in the spinal canal are only identified though a post-surgical analysis of the mass. Though no definitive correlation can be presently made, there is increasing evidence for a relationship between autoimmune diseases and IPTs. IPT should be included in the differential diagnosis in patients with previous autoimmune disease that present with unexplained mass in the CNS.

Patient Care: This case report will improve consideration of IPTs as a differential in spinal masses in a patient with a history of autoimmune disorders.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) appreciate the potential of inflammatory pseudotumors in the CNS, 2) Discuss potential methods to differentiate IPTs from neoplastic growths before surgical resection

References: 1. Aizawa T, Sato T, Tanaka Y, Kishimoto K, Watanabe M, Kokubun S: Intramedullary plasma cell granuloma in the cervicothoracic spine. Case report. J Neurosurg 97:235-238, 2002 2. Andrade DM, Martins SJ, Paz O, Cardozo JB, Novaes AE, Santiago MB: Inflammatory pseudotumor: A diagnostic dilemma. Eur J Intern Med 17:514-516, 2006 3. Gilliard C, De Coene B, Lahdou JB, Boutsen Y, Noel H, Godfraind C: Cervical epidural pseudotumor and multifocal fibrosclerosis. Case report and review of the literature. J Neurosurg 93:152-156, 2000