Background
Retrospective, multicenter pooled analysis from 3 German centers (TU Munich, Heidelberg, Freiburg). 449 patients, 451 vestibular schwannomas (VS) treated with single-fraction SRS (n=169; 38%) or fractionated stereotactic RT (FSRT; n=291; 62%). Median tumor diameter 15 mm (range 3–42 mm). Objective: compare long-term local control and hearing preservation between SRS and FSRT.
Interventions and follow up
Arm A (SRS): Single-fraction stereotactic radiosurgery, median dose 13 Gy (n=169)
Arm B (FSRT): Fractionated stereotactic RT, median 57.6 Gy in 1.8 Gy fractions (n=291)
Primary endpoint: Local control, hearing preservation, cranial nerve toxicity
mFollow up: Median 67 months
Arm B (FSRT): Fractionated stereotactic RT, median 57.6 Gy in 1.8 Gy fractions (n=291)
Primary endpoint: Local control, hearing preservation, cranial nerve toxicity
mFollow up: Median 67 months
Results
Local control at 36 months: 97% (no significant difference SRS vs FSRT, P=.39)
Local control at 60 months: 95%
Local control at 120 months: 94%
Useful hearing preservation: 85% overall; loss 13–16% in both arms
Trigeminal/facial nerve toxicity: No difference between SRS and FSRT
Local control at 60 months: 95%
Local control at 120 months: 94%
Useful hearing preservation: 85% overall; loss 13–16% in both arms
Trigeminal/facial nerve toxicity: No difference between SRS and FSRT
Adverse events
Trigeminal neuropathy: 2.7% (SRS) vs 1.7% (FSRT)
New facial nerve palsy: <2% both arms
Hearing deterioration from baseline: 13% SRS ≤13 Gy vs 14% FSRT
Brainstem toxicity grade ≥2: None reported
New facial nerve palsy: <2% both arms
Hearing deterioration from baseline: 13% SRS ≤13 Gy vs 14% FSRT
Brainstem toxicity grade ≥2: None reported
Conclusions
Both SRS (≤13 Gy) and FSRT (57.6 Gy) achieve equivalent, excellent local control exceeding 94% at 10 years for vestibular schwannoma, with no clinically meaningful difference in hearing preservation or cranial nerve toxicity. Treatment choice can be based on tumor size, pre-treatment hearing, and patient preference.
Key Limitations
Retrospective, non-randomized — treatment allocation (SRS vs FSRT) driven by tumor size and hearing status, confounding direct comparison. Pooled across centers with technique heterogeneity. Hearing outcomes limited to patients with serviceable baseline hearing; no quality-of-life endpoints.
Clinical Context
Large long-term dataset supporting both SRS and FSRT as durable, low-morbidity options for vestibular schwannoma. SRS favored for smaller tumors; FSRT often chosen for larger tumors or those abutting critical structures to limit single-fraction toxicity. Reinforces radiation as an alternative to microsurgical resection in appropriately selected VS.