Retrospective analysis of peripheral nerve sheath tumors of the second cervical nerve root in 60 surgically treated patients

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>This study is a retrospective analysis of 60 surgically treated patients with 64 peripheral nerve sheath tumors (PNSTs) at the second cervical (C-2) nerve root. The anatomical subtleties of these tumors and their implications for surgical strategy when compared with other spinal PNSTs and other tumors in the foramen magnum region are reviewed.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>Sixty patients with C-2 PNSTs treated surgically in the Department of Neurosurgery at King Edward VII Memorial Hospital and Seth Gordhandas Sunderdas Medical College between 1992 and 2006 were studied. All patients underwent magnetic resonance imaging. Tumors were divided into 3 groups depending on their anatomical location identified during surgery. Those tumors located within or extending into the spinal dural tube were called Type A, those located within the dural tube of the C-2 ganglion were labeled as Type B, and tumors extending laterally into the paraspinal region were labeled as Type C. Follow-up durations ranged from 6 months to 15 years (mean 64 months).</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>There were 38 male and 22 female patients in the study, who ranged in age from 6 to 62 years (mean 28 years). Nine patients had clinical features indicative of neurofibromatosis (NF). The mean duration of symptoms at the time of presentation was 27 months (range 4 days–5 years). Two patients had no specific symptoms related to the C-2 PNST, 6 patients had only local symptoms such as neck pain or stiffness, and 52 patients had symptoms of varying degrees of myelopathy. There were 5 solely Type A tumors, 7 Type A + B tumors, 31 Type B tumors, and 21 Type B + C tumors. All Type A, A + B, and B tumors were totally resected. Seven of 21 Type B + C tumors were partially resected, and the remainder were completely resected. All patients postoperatively reported varying improvement in their preoperative symptoms. Except for patients with NF who were disabled by other tumors, the rest of the patients resumed their normal life style. There have been no cases of symptomatic tumor recurrence.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>The majority of PNSTs located at the C-2 level in these patients probably arose from the large C-2 ganglion and are limited within the dural confines or are interdural in location. In contrast to other spinal PNSTs, the location of C-2 PNSTs is in most cases posterior to the lateral mass of the atlas and axis and the atlantoaxial joint and is exposed to the posterior without any bone cover. Radical tumor resection is safe, resolution of clinical symptoms is rapid, and recurrence rates are extremely low. In a selected number of cases, bone work for tumor exposure and resection can be entirely avoided.</jats:p></jats:sec>

Surgery of Spinal Nerve Sheath Tumors Originating From C1 or C2 of High Cervical Spine -Technical Note-

“…Therefore, working within the dural confines and respecting the dural cover of the tumor can lead to radical and safe tumor resection. We think that such surgical technique may be insufficient and needs to be modified in the case of extensive extension to the paraspinal region, such as Type C. [1][2][3]8,11,15) In our series, we encountered a single case of spinal NST originating from C1 not associated with neurofibromatosis. Non-neurofibromatosis NSTs originating from C1 are extremely rare.…”

“…Various surgical approaches have been applied to resect dumbbell-shaped or extradural tumors of the cervical spine, but excessive bone resection and soft tissue T. Takami et al manipulation appear to be unnecessary in the majority of spinal NSTs originating from the C1 or C2 level. [2][3][4]8,9,11,15) In an exceptional case, another surgical strategy such as an anterolateral approach with management of vertebral artery may be adequate to resect tumor involving the vertebral artery or extending beyond the vertebral artery, which is one of the limiting factors of the radical resection. 2,15) Excessive bone resection for wide exposure of the tumor may necessitate a subsequent fusion procedure such as posterior occipitocervical or C1-2 fixation.…”

“…A series of 64 spinal NSTs originating from the C2 were divided into 3 types based on their anatomical location and relationship with the dura, as identified during surgery. 3) Type A tumors were located within or extended into the spinal dural tube. These tumors extended anterolaterally or anteriorly to the cord.…”

“…1,5,7,13,14) Although spinal NSTs with extradural components may affect any cervical nerve root, higher prevalence at the C2 level is expected compared to other cervical levels. 2,3,5,10,13) The C1 and C2 spinal levels are anatomically exceptional because no intervertebral foramens are located at these levels. The facet joint lies anterior to the nerve roots of C1 and C2 as they exit and penetrate the dura at the occipitocervical and atlantoaxial levels, resulting in exuberant growth of the tumor.…”

Laminoplasty using the posterior midline approach in the treatment of c1-2 spinal tumors

“…Many clinicians believe that the reconstruction of cervical spine instability is an important aspect of high cervical spinal tumor treatment (12,18,24). According to Goel, because C2 schwannomas are in most cases located at the ganglion and are subdural, and because they are located between the atlas and atlantoaxial joint, as well as inside the atlantoaxial joint, resection of the atlantoaxial posterior arch and vertebral body to fully expose and remove the tumor is not required (9). In this group of patients, we found that the C1-2 spinal bodies were wider, and the average sagittal diameter was 20-23 mm (14).…”