Cervical Intramedullary Schwannoma: Case Report and Review of the Literature

Abstract

Cervical intramedullary schwannomas are extraordinarily rare. Gross total resection is the best therapeutic option for these types of tumors. Although rare, intramedullary schwannomas should be considered as a differential diagnosis of intramedullary lesions since a good prognosis can be guaranteed to the majority of these patients. We present a case of a cervical intramedullary schwannoma surgically treated in a 19-year-old male patient who initially presented with motor neuron disease.

Intradural Extramedullary Spinal Neoplasms: Radiologic-Pathologic Correlation

“…Rarely (about 1.1% of spinal schwannomas), the tumor may arise in the spinal cord, usually the cervical spinal cord (63%). Intramedullary schwannoma has a male predilection (3:1) with a mean age of presentation in the 4th decade (29). Given the lack of Schwann cells in the spinal cord under normal circumstances, a wide variety of theories (dorsal nerve root entry zone origin, subpial extension along the perivascular nerve plexus, ectopic neural crest, differentiated Schwann cells from mesenchymal CNS elements, proliferation of Schwann cells after trauma or inflammatory disease) have been proposed, but the histogenesis remains controversial (30).…”

“…Intramedullary schwannoma manifests as a well-demarcated spinal cord mass with intense enhancement that may be ringlike in morphology but is difficult to confidently differentiate from other intramedullary neoplasms in most circumstances (29,30). When present, a thickened enhancing adjacent nerve root should increase suspicion for the tumor (36).…”

Rare Case of Multiple Intradural Extramedullary Spinal Schwannomas With Intramedullary Extension

“…These lesions exhibit an eccentric growth pattern, with the nerve fiber itself usually being incorporated into the tumor capsule. These lesions are considered the most common tumors of peripheral nerves, accounting for nearly one-third of all spinal neoplasm [ 1 , 2 ]. The vast majority of schwannomas (90-95%) remain solitary and sporadic, whereas a rare but characteristic association with NF2 and schwannomatosis has been described [ 1 , 3 - 5 ].…”

“…The characteristic lack of an intramedullary component has been historically attributed to the fact that Schwann cells do not routinely exist within the spinal cord [ 6 , 7 ]. Unlike their extramedullary counterparts, intramedullary schwannomas exhibit a 3:1 male predilection and present relatively earlier in the fourth decade of life [ 2 , 3 ]. Given the lack of Schwann cells in the normal spinal cord, various theories have been postulated to explain the occurrence of such intramedullary spinal component.…”

“…Unlike its classical extramedullary counterpart, when such intramedullary extension is present, these neoplasms express a male-to-female ratio of 3:1 and preferentially present in the fourth decade of life. The possession of an intramedullary component makes differentiating such spinal schwannomas from other intramedullary spinal neoplasms a radiological challenge, and thus it is of great importance to review the imaging characteristics and presentation of such a rare entity [ 1 , 2 ].…”