Long-term outcomes of staged Gamma Knife radiosurgery for giant cavernous sinus hemangiomas: a single-center retrospective study

OBJECTIVE Cavernous sinus hemangiomas (CSHs) are rare benign tumors originating from the cavernous sinus. Gamma Knife radiosurgery (GKRS) has been recommended as a primary treatment for small- to medium-sized CSHs. The optimal treatment for giant CSHs is still controversial. In this study, the authors retrospectively reviewed the effectiveness and safety of staged GKRS treatment for giant CSHs. METHODS Twenty-two patients with giant CSH who received staged GKRS treatment in the Gamma Knife Treatment Center of Henan Province during the period from January 1, 2011, to December 31, 2018, were enrolled in this study. Six patients had received microsurgery before GKRS, the other 16 patients were diagnosed according to clinical symptoms and MR images. All of the enrolled patients received 2-stage GKRS, and the mean interval between the two GKRS treatments was 6.5 months (range 6-12 months). For the first GKRS, the median isodose line was 48% (range 45%-50%), the median marginal dose was 13 Gy (range 11.5-14 Gy), and the median coverage of CSHs was 80% (range 70%-88%). For the second GKRS treatment, the median isodose line was 50% (range 45%- 55%), the median marginal dose to the CSHs was 10.5 Gy (range 9-12.5 Gy), and the median coverage of the CSHs was 88% (range 80%-94%). RESULTS All of the patients received an outpatient review of an enhanced MR image of the head and a clinical physical check every 6 months after the first GKRS treatment. The mean follow-up duration was 52 months (range 24-84 months). The tumor control rate was 100% 24 months after staged GKRS, and at the last follow-up the mean tumor shrinkage rate was 96.7% (range 90.6%-100%) and the mean residual CSH volume was 2.1 ml (range 0-8.5 ml). Twenty patients suffered central nervous system (CNS) injury symptoms to varying degrees before staged GKRS treatment. Complete symptom recovery was found in 11 (55%) patients, improved symptoms in 5 (25%) patients, and no change in 4 (20%) patients after treatment. Only 1 patient suffered temporary preexisting headache aggravation and 1 patient suffered temporary preexisting diplopia aggravation 1 week after receiving the first GKRS treatment. Subacute or chronic complications were not detected after staged GKRS. CONCLUSIONS Staged GKRS is an effective treatment for giant CSHs. Because of the impressively low incidence of adverse effects, staged GKRS may be considered as a primary treatment for giant CSHs.