Tumor Control After Radiosurgery in Sporadic and Neurofibromatosis Type 2 Vestibular Schwannomas

Abstract

Introduction The tumor control rate after stereotactic radiosurgery (SRS) for neurofibromatosis type 2-associated vestibular schwannomas (NF2-VSs) compared to sporadic vestibular schwannomas (S-VSs) remains unclear. This nationwide, multicenter, retrospective study (KGKRS-21-001) aimed to clarify this issue. Methods A total of 4718 patients treated with SRS for vestibular schwannomas were analyzed from 13 nationwide institutions in Korea. NF2-VS cases were propensity score-matched with S-VS cases at a ratio of 1:1, based on age, tumor volume, and marginal dose, resulting in 122 cases in each group. Results No significant differences in age, tumor volume, or marginal dose were observed between the matched cohorts. The overall tumor control rates at 1, 3, and 10 years after SRS were 93.3%, 87.7%, and 80.7%, respectively, with no significant difference between NF2-VS and S-VS groups (p = 0.63). Subgroup analysis showed that age <= 19 years was a significant negative prognostic factor for tumor control in NF2-VS patients (p < 0.001), whereas no such correlation was found in the S-VS cohort (p = 0.78). Conclusions SRS provides comparable tumor control for NF2-VSs and S-VSs. However, among NF2-VS patients, younger age (<= 19 years) was associated with poorer tumor control, suggesting that age may be a critical factor in treatment decisions.