The biological underpinnings of radiation therapy for vestibular schwannomas: Review of the literature

OBJECTIVE: Radiation therapy is a mainstay in the treatment of numerous neoplasms. Numerous publications have reported good clinical outcomes for primary radiation therapy for Vestibular Schwannomas (VS). However, there are relatively few pathologic specimens of VSs available to evaluate post‐radiation, which has led to a relative dearth in research on the cellular mechanisms underlying the effects of radiation therapy on VSs. METHODS: Here we review the latest literature on the complex biological effects of radiation therapy on these benign tumors—including resistance to oxidative stress, mechanisms of DNA damage repair, alterations in normal growth factor pathways, changes in surrounding vasculature, and alterations in immune responses following radiation. RESULTS: Although VSs are highly radioresistant, radiotherapy is often successful in arresting their growth. CONCLUSION: By better understanding the mechanisms underlying these effects, we could potentially harness such mechanisms in the future to potentiate the clinical effects of radiotherapy on VSs. LEVEL OF EVIDENCE: N/A.