Gamma Knife Radiosurgery in Sphenopetroclival Meningiomas: Preliminary Experience at the Iran Gamma Knife Center

Objective The aims of this study were to characterize the epidemiologic, histologic, and radiologic aspects of sphenopetroclival meningiomas (SpPCMs) and to evaluate the outcome of Gamma Knife radiosurgery (GKRS) either as an adjunct to microsurgery or as a primary SpPCM treatment modality. Methods In this retrospective study, medical records of patients with SpPCM who underwent GKRS at the Iran Gamma Knife Center between April 2003 and March 2012 were analyzed. Results We assessed 122 patients with SpPCMs, including 101 women and 21 men, aged 24-94 years. The mean tumor volume was 12.24 ± 9.30 mL. Patients received 22.32 ± 3.29 Gy and 13.18 ± 1.02 Gy maximal and average marginal dose of GKRS, respectively. The most common complaint was visual impairment, followed by facial sensory impairment and headache. The most frequently involved cranial nerves were III, IV, and VI in 72.1 of patients, followed by II in 52.9, and V in 35.5. After radiosurgery, headaches improved in 90.0, diplopia in 75.0, and ptosis in 63.0 of patients. On magnetic resonance imaging, tumor size was reduced, unchanged, or increased in 77, 44, and 1 patient, respectively. Progression-free survival at the 5-year follow-up was 56.6. Younger age (hazard ratio = 0.972, P = 0.011) and lower tumor volume (hazard ratio = 0.959, P = 0.009) were the main prognostic factors for progression-free survival. Conclusion GKRS can be an effective alternative treatment for controlling the progression of SpPCM tumors, producing appropriate clinical outcomes and few complications. © 2016 Elsevier Inc