BACKGROUND: Because of their rarity, outcomes regarding spinal atypical 
meningiomas (AMs) remain unclear.
OBJECTIVE: To describe the recurrence rate and postoperative outcomes after 
resection of spinal AMs, and to discuss an appropriate resection strategy and 
adjuvant therapy for spinal AMs.
METHODS: Data from all patients who presented with spinal AMs to 2 tertiary 
referral centers between 1998 and 2013 were obtained by chart review.
RESULTS: From 102 patients with spinal meningioma, 20 AM tumors (7 cervical, 11 
thoracic, 2 thoracolumbar) were identified in 18 patients (median age, 50 years 
[range, 19-75] at time of resection; 11% male; median follow-up, 32 months 
[range, 1-179] after resection). Before resection, patients had sensory deficits 
(70%), pain (70%), weakness (60%), ataxia (50%), spasticity (65%), and 
incontinence (35%). One tumor presented asymptomatically. Simpson grade I, II, 
III, and IV resection were achieved in 3 (15%), 13 (65%), 2 (10%), and 2 (10%) 
tumors, respectively. One patient that underwent Simpson grade III resection 
received adjuvant radiation therapy. After Simpson grade I-III or gross total 
resection, no tumors recurred (0%; confidence interval, 0%-17.6%). After Simpson 
grade IV resection, 1 tumor recurred (50%; confidence interval, 1.3%-98.7%). 
With the exception of 1 patient who had bilateral paraplegia perioperatively, 
all other patients experienced improvement of preoperative symptoms after 
surgery (median time, 3.6 months [range, 1-13] after resection).
CONCLUSION: Despite published cases suggesting an aggressive clinical course for 
spinal AMs, this series of spinal AMs reports that gross total resection without 
adjuvant radiation therapy resulted in symptom resolution and low recurrence.