Spinal neurinomas: retrospective analysis and long-term outcome of 179 consecutively operated cases and review of the literature.

Background: We present a series of 179 spinal neurinomas consecutively observed at the Department of Neurosurgery at the University of Florence for a period of 30 years (between 1967 and 1997). We decided to limit the retrospective study to obtain at least 5 years of follow-up. Therefore, 20 additional neurinomas treated between 1997 and 2002 were excluded.

Methods: All the cases are evaluated under statistical, clinical, neuroradiological, and surgically technical profiles based on data from clinical records and from periodic check-ups after surgery. In particular, the results are analyzed on the basis of an accurate pre- and postsurgical evaluation using Karnofsky's scale and Kleklamp-Samii's scoring system.

Results: We treated 179 spinal neurinomas in 152 (93 male and 59 female) patients. The mean age was 44.3. In 33 cases the neurinoma was sited in the cervical tract, in 59 cases in the dorsal tract, and in 87 cases in the lumbo-sacral tract. Eleven patients harbored Recklinghausen's neurofibromatosis (7 NF1 and 4 NF2 of which 1 was intramedullary). In 123 cases the neurinoma was intradural, in 11 cases it was extradural, in 2 intra/extradural, in 9 it had a dumbbell form, and in 2 cases it was intramedullary; the remaining cases had neurofibromatosis. The most common presurgical symptom was segmental pain. Total removal of the lesion was possible in the first operation for 174 neurinomas. We encountered 3 cases of malignant neurinoma of which 1 was in NF2. The result of surgery was recovery in 108 cases; 2 patients with NF2 died, and local recurrence occurred even after total exeresis (excision) and radiotherapy in the cases of malignant neurinoma.

Conclusions: Schwannomas represent the most frequent tumor lesions of the spine with prevalence for the cervical-inferior tract and the dorso-lumbar passage. Intramedullary neurinomas are rarely observed. The total surgical removal of neurinomas is often an attainable goal, and clinical improvement is the common outcome with exception to malignant forms and NF2 neurofibromatosis. We describe a series of 179 treated schwannomas.