LAUSR

OBJECTIVE Vestibular schwannomas (VS) can either be solid or contain variable amounts of cystic components. It is established that gamma knife radiosurgery (GKS) was an effective treatment modality for solid VS. However, in case of the cystic VS, Given the somewhat unpredictable growth of the cystic portion of these tumors, microsurgery is often preferred to GKS in the management of cystic VS. However, to date, there is a relative paucity of data evaluating outcomes after GKS for cystic VS. In the present study, we reviewed our experience treating cystic VSs with GKS and evaluated results. METHODS Patients diagnosed with cystic VS who were treated with GKRS between 1999 and 2018 were analyzed. Only patients who received GKS as an initial treatment for cystic VSs were included in the study and patients who underwent prior surgical treatment were excluded. Cystic VSs were divided into intra-tumoral cyst and extra-tumoral cyst. RESULTS A total of 24 patients were enrolled in the current study. The mean age was 60.8 ± 2.4 years old (range: 38-82). The mean follow-up periods was 55.8 ± 8.1 months (range: 8-145). Eleven patients were male. The control rate of GKS for cystic VSs was 75%. Five years progress-free rate was 70%. Six patients were presented increased lesion after GKS. Among them, two patients underwent surgical treatment and one patient was received repeat GKS. There was no statistical significance between control rate and cystic type (p=0.093). CONCLUSION The present study demonstrated that GKS was an effective treatment modality for cystic VS.