Surgery of intramedullary tumors is established as the treatment of choice for these challenging lesions. This study presents a detailed analysis of risk factors for surgical morbidity and data on long-term results for intramedullary tumors.
Among 1317 patients with tumors of the spinal canal treated between 1980 and 2012, 278 patients with intramedullary tumors are presented. A total of 225 of these patients underwent 246 operations for treatment of 250 tumors. The mean patient age was 41 ± 17 years (range 3 weeks to 83 years). Patients underwent follow-up through outpatient visits and questionnaires with a mean follow-up of 41 ± 53 months. Tumors were subdivided into 3 groups: displacing tumors (Type A, n = 162), infiltrating tumors (Type B, n = 80), and nonproliferating tumors (Type C, n = 8). A gross-total resection (GTR) was attempted for every tumor except for Type C lipomas. Participating surgeons were divided into 3 groups according to the number of operations they performed. Short-term results were determined for individual symptoms and the modified McCormick Scale, whereas tumor recurrence rates were calculated with Kaplan-Meier statistics.
Overall, 83.3% of Type A tumors underwent GTR compared with 22.5% of Type B and none in Type C. Gross-total resection rates increased throughout the study period and correlated significantly with surgical experience. A worsened neurological state after surgery was seen in 61% of patients. This deterioration was transient in 41.5% and was a common observation after GTR. Permanent morbidity (19.5%) was lowest after GTR and correlated significantly with surgical experience and the preoperative neurological state. Further analysis showed that patients with tumors of thoracic levels, tumor hemorrhages, and malignant and recurrent tumors were at a higher risk for permanent morbidity. In the long term, tumor recurrence rates for ependymomas and benign astrocytomas correlated significantly with the amount of resection. Long-term morbidity affected 3.7% with a postoperative myelopathy related to cord tethering at the level of surgery and 21.9% in form of neuropathic pain syndromes. The rate of postsurgical cord tethering could be lowered significantly by using pia sutures after tumor resection. Neuropathic pain syndromes were more common after surgery for tumors with associated syringomyelia or those located in the cervical cord.
Intramedullary tumors should be surgically treated as soon as neurological symptoms appear. Gross-total resection is possible for the majority of benign pathologies. Cervical tumors are associated with higher GTR and lower permanent morbidity rates compared with thoracic tumors. Surgery on intramedullary tumors should be performed by neurosurgeons who deal with these lesions on a regular basis as considerable experience is required to achieve high GTR rates and to limit rates of permanent morbidity.
Abbreviations used in this paper:GTR = gross-total resection; PR = partial resection; STR = subtotal resection; VHL = von Hippel-Lindau.
AghakhaniNDavidPParkerFLacroixCBenoudibaFTadieM: Intramedullary spinal ependymomas: analysis of a consecutive series of 82 adult cases with particular attention to patients with no preoperative neurological deficit. Neurosurgery62:1279–12862008
Bernal-GarcíaLMCabezudo-ArteroJMOrtega-MartínezMPorras-EstradaLFFernández-PortalesIUgarriza-EchebarrietaLF: [Intramedullary schwannomas. Report of two cases.]. Neurocirugia (Astur)21:232–2392010. (Span)
EbnerFHRoserFFalkMHermannSHoneggerJTatagibaM: Management of intramedullary spinal cord lesions: interdependence of the longitudinal extension of the lesion and the functional outcome. Eur Spine J19:665–6692010
KarikariIONimjeeSMHodgesTRCutrellEHughesBDPowersCJ: Impact of tumor histology on resectability and neurological outcome in primary intramedullary spinal cord tumors: a single-center experience with 102 patients. Neurosurgery68:188–1972011
MehtaGUAsthagiriARBakhtianKDAuhSOldfieldEHLonserRR: Functional outcome after resection of spinal cord hemangioblastomas associated with von Hippel-Lindau disease. Clinical article. J Neurosurg Spine12:233–2422010
NakamuraMChibaKNishizawaTMaruiwaHMatsumotoMToyamaY: Retrospective study of surgery-related outcomes in patients with syringomyelia associated with Chiari I malformation: clinical significance of changes in the size and localization of syrinx on pain relief. J Neurosurg100:3 Suppl Spine241–2442004
SamuelsRMcGirtMJAttenelloFJGarcés AmbrossiGLSinghNSolakogluC: Incidence of symptomatic retethering after surgical management of pediatric tethered cord syndrome with or without duraplasty. Childs Nerv Syst25:1085–10892009
SteigerHJTurowskiBHänggiD: Prognostic factors for the outcome of surgical and conservative treatment of symptomatic spinal cord cavernous malformations: a review of a series of 20 patients. Neurosurg Focus29:3E132010