Long-term surgical outcomes of cervical dumbbell neurinomas

Study design: Retrospective case series. Objective: To evaluate our treatment strategy for cervical dumbbell neurinoma. Summary of background data: In treating cervical dumbbell neurinoma, possible difficulties include reoperation due to recurrent tumor, denervation due to nerve root resection, and postoperative spinal deformity due to extensive bony removal. Methods: We reviewed 75 cases of cervical dumbbell neurinoma that were treated surgically between 1985 and 2006. Postoperative neurological deficits, effects of surgical margins on tumor recurrence, and surgical complications were investigated retrospectively. Results: Sensory and motor deficits due to resection of specific nerve roots appeared temporarily in 33 and 23 % of all cases, and persisted in 8 and 8 % at final evaluation, respectively. Total, subtotal, and partial resection was performed in 57, 13, and 5 cases, respectively. The total resection rate was low in the tumors that had large extraforaminal components. Of the subtotally resected 13 cases, only two cases of high tumor-growth rate required re-operation or showed tumor growth. Among the five partially resected cases, re-operation was necessary in two cases 13 and 15 years later because of aggravated neurological symptoms due to tumor growth. Two patients who underwent C2 laminectomy developed kyphosis, and three patients who underwent facet joint resection and curettage of vertebral body lesions developed scoliosis. Conclusion: Total resection should be attempted for cervical dumbbell tumors. In cases where total resection was potentially of high risk, however, subtotal resection (within the capsule) was found to be a practical choice yielding favorable long-term outcome when the tumor growth rate (MIB-1 index) was low.