INTRAAXIAL TUMORS OF THE CERVICOMEDULLARY JUNCTION - SURGICAL RESULTSAND LONG-TERM OUTCOME

Until recently, intra-axial brainstem tumors were traditionally regard ed as surgically inaccessible lesions with a uniformly poor prognosis. However, increasing data indicate that distinct subgroups of brainste m tumors exist that are amenable to surgical intervention. To address this question, we reviewed our experience in the operative management of 39 consecutive patients, in the magnetic resonance imaging (MRI) er a, with intra-axial cervicomedullary tumors, in order to determine tho se factors associated with long-term outcome. Thirty-nine patients (26 male, 13 female) underwent surgery by a single surgeon (F.J.E.) betwe en 1985 and 1994. Mean age of diagnosis was 14 years (range 3 months - 60 years); mean duration of preoperative symptoms was 24 weeks (range 1 - 168). Twenty patients presented with lower cranial nerve dysfunct ion and 19 presented with motor and/or sensory dysfunction. All patien ts were graded according to the McCormick Scale, pre-and postoperative ly, and at the time of follow-up. All patients were evaluated with MRI scanning. Twenty-three patients had either previous biopsy or subtota l resection, 13 previous radiation therapy, and 6 previous chemotherap y. The mean time to follow-up was 48 months (range 7 - 138). Twelve pa tients underwent gross total resection, 7 near total resection (> 90%) , 15 subtotal resection (50 - 90%), and 5 partial resection (< 50%). H istologically, there were 15 low-grade fibrillary astrocytomas, 9 epen dymomas, 7 gangliogliomas, 3 anaplastic astrocytomas, 3 juvenile piloc ytic astrocytomas, and 2 mixed gliomas. Although the vast majority of tumors were low grade histologically, a higher proportion of the patie nts with high-grade lesions experienced tumor progression when compare d to low-grade tumors (75 vs. 30%). Overall, the 5-year progression-fr ee and total survivals were 60 and 89%, respectively. There was 1 deat h within the first postoperative month. Preoperative duration of sympt oms greater than 15 weeks was associated with a longer progression-fre e survival. There was a trend for preoperative neurologic grade to pre dict functional neurologic outcome at follow-up. In summary, intra-axi al tumors of the cervicomedullary junction are a distinct subset of br ainstem tumors, predominantly of low-grade histology, with favorable l ong-term progression-free and total survivals following surgical resec tion. A long duration of preoperative symptoms may indicate an indolen t clinical course and a more favorable prognosis. Our data also indica te that early surgical intervention is warranted prior to neurologic d eterioration.