Introduction: Because of their rarity, outcomes regarding spinal atypical meningiomas (AMs) remain unclear; of 725 patients with spinal meningioma described in the 2000-2013 literature, only 15 had AMs. This study reports outcomes after resection of AMs in 17 patients.
Methods: Data from all patients who presented with spinal AMs to two tertiary referral centers between 1998 and 2013 were obtained by chart review.
Results: From 102 patients with spinal meningioma, 20 AM tumors [7 cervical, 12 thoracic, 1 lumbar] were identified in 17 patients [median age 42 (range, 19-75) at time of resection, 18% male, median follow-up 34 months (range, 1-171) following resection]. Simpson grade I, II, III, and IV resection were achieved in 4 (20%), 14 (70%), 1 (5%), and 1 (5%) tumors, respectively. One patient that underwent grade II resection received adjuvant radiation therapy. After grade I, II, and III resection, zero tumors recurred. After grade IV resection, one tumor recurred (100%). In all but four patients, data regarding postoperative functional status were available. Before resection, 13 (65%), 11 (55%), 11 (55%), 8 (40%), 5 (25%), and 4 (20%) tumors caused sensory deficits, pain, weakness, gait ataxia, upper motor neuron signs, and incontinence, respectively. One tumor presented asymptomatically. Postoperatively (median time 3.6 months [range, 1-13 months] after resection), 0 (0%), 6 (38%), 2 (13%), 1 (6%), 0 (0%), and 0 (0%) tumors caused sensory deficits, pain, weakness, gait ataxia, upper motor neuron signs, and incontinence, respectively. In all patients with post-operative follow-up data, functional status improved after surgery.
Conclusions: Despite published cases suggesting an aggressive clinical course for spinal AMs, this series of spinal atypical meningiomas indicates that Simpson grade II resection without adjuvant radiation therapy can result in rapid symptom resolution and low recurrence.
Patient Care: Currently, spinal atypical meningiomas are treated aggressively with Simpson grade I-III resection and adjuvant radiation therapy. Our study suggests that Simpson grade II resection alone is sufficient to achieve 100% local control over a median follow-up time of 34 months.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the recurrence rate and postoperative outcomes following resection of spinal atypical meningiomas, 2) Discuss, in small groups, the appropriate resection strategy and adjuvant therapy for spinal atypical meningiomas