Linear Accelerator-Based Radiosurgery of Grade I Intracranial Meningiomas

World Neurosurg X. 2019 Mar 7:3:100027. doi: 10.1016/j.wnsx.2019.100027. eCollection 2019 Jul.

Abstract

Objective: To determine the local control rate and complication rate in the treatment of grade I intracranial meningiomas.

Methods: A retrospective study was performed of patients with grade I meningioma who received radiosurgery with a dedicated linear accelerator from January 2002 to August 2012 with a minimum follow-up of 2 years. We performed descriptive statistics, logistic regression, and progression-free survival analysis through a Kaplan-Meier curve.

Results: Seventy-five patients with 78 grade I meningiomas received radiosurgery, 39 underwent surgery plus adjuvant radiosurgery, and 36 only radiosurgery. The follow-up median time was 68 months (range, 35-120 months). The tumor control rate was 93%, the 5-year progression-free survival was 92% (95% confidence interval, 77%-98%). Acute toxicity was 2.6%, and grade 1-2 late toxicity was 26.6%. Postradiosurgery edema was the main late morbidity. Age >55 years was the only significant factor for attaining a response >75%. The background of surgery before radiosurgery was the only significant prognostic factor for showing edema (odds ratio 5.78 [95% confidence interval, 2.14-15.64]).

Conclusions: The local control rate attained in our series is similar to that reported in other series worldwide; the acute toxicity rate was low and late toxicity was moderate.

Keywords: Benign tumors; CBK, CyberKnife; GKRS, Gamma Knife radiosurgery; LINAC radiosurgery; LINAC, Linear accelerator; MRI, Magnetic resonance imaging; Meningiomas; PFS, Progression-free survival; RS, Radiosurgery; WHO, World Health Organization.