Stereotactic Radiosurgery Versus Observation in Small- and Medium-Sized Vestibular Schwannoma Patients With Normal Hearing: A Retrospective International Multicenter Study

Neurosurgery 98:887–894, 2026

This multicenter retrospective study compares stereotactic radiosurgery (SRS) with observation (OBS) for small-to-medium vestibular schwannomas (Koos I–II) in patients presenting with normal (AAO‑HNS class A) hearing. Propensity-score–matched cohorts (57 SRS, 57 OBS) were analyzed for serviceable hearing preservation (SHP), tumor control (TC), and cranial nerve outcomes over median follow-ups of 49 and 37 months.

Results show SRS achieved markedly superior tumor control (≈98% at 5–10 years) while producing noninferior hearing outcomes versus observation (5‑year SHP: SRS 76.2% vs OBS 56.1%; difference not statistically significant). The authors conclude SRS is preferable for TC without compromising hearing, emphasizing individualized decision-making given study limitations.

Clinical question Comparison of stereotactic radiosurgery (SRS) vs observation (OBS) for small/medium Koos I–II vestibular schwannomas in patients with AAO-HNS class A (normal) hearing at presentation, focusing on hearing preservation and tumor control

Design Retrospective international multicenter study with propensity score matching (age, sex, tumor volume, PTA, SDS) yielding 57 SRS vs 57 OBS matched patients

Serviceable hearing preservation No statistically significant difference in long-term serviceable hearing preservation between SRS and OBS in the matched analysis (log-rank P = .17), despite numerically higher SRS rates

Hearing rates over time Matched-cohort 5-/9-year serviceable hearing preservation: SRS 76.2% / 42.4% vs OBS 56.1% / 16.8%

Class A hearing Class A preservation was similar: 57.9% (SRS) vs 52.6% (OBS) (P = .70)

Tumor control SRS achieved markedly superior tumor control (log-rank P < .0001); 5-/10-year tumor control: SRS 97.9% / 97.9% vs OBS 40.9% / 15.1%

Other clinical outcomes No significant matched-cohort differences in cranial nerve deficits, vestibulopathy, or composite CN/tinnitus worsening; tinnitus worsening trended higher with OBS (21.1% vs 8.8%) but was not significant (P = .066)

Overall conclusion SRS provided noninferior hearing outcomes while being significantly better for tumor control, supporting SRS as a favored option while still emphasizing individualized decision-making