Background
Single-institution retrospective (Heidelberg). N=200 vestibular schwannoma treated with LINAC-based SRS (n=96) or FSRT (n=104), 1992–2005. SRS for smaller tumors; FSRT for larger/hearing-critical cases.
Interventions and follow up
Arm A (LINAC SRS): Single-fraction LINAC SRS, frame-based positioning (n=96)
Arm B (FSRT): Fractionated stereotactic RT (n=104)
Primary endpoint: Local control (MRI-defined), hearing preservation
mFollow up: Median SRS 75.5 mo; FSRT 52.0 mo
Arm B (FSRT): Fractionated stereotactic RT (n=104)
Primary endpoint: Local control (MRI-defined), hearing preservation
mFollow up: Median SRS 75.5 mo; FSRT 52.0 mo
Results
5-yr local control (SRS): 97.5%
5-yr local control (FSRT): 97.5%
Serviceable hearing preserved (SRS): 73%
Serviceable hearing preserved (FSRT): 80%
Facial nerve toxicity (>HB grade II): 2.1% (SRS) vs 1.0% (FSRT)
5-yr local control (FSRT): 97.5%
Serviceable hearing preserved (SRS): 73%
Serviceable hearing preserved (FSRT): 80%
Facial nerve toxicity (>HB grade II): 2.1% (SRS) vs 1.0% (FSRT)
Adverse events
Trigeminal neuropathy: 3.1% (SRS) vs 1.0% (FSRT)
Facial nerve new palsy: 2.1% (SRS) vs 1.0% (FSRT)
Symptomatic peritumoral edema: 4.2% (SRS) vs 0% (FSRT)
Grade 4–5: None; both modalities well tolerated
Facial nerve new palsy: 2.1% (SRS) vs 1.0% (FSRT)
Symptomatic peritumoral edema: 4.2% (SRS) vs 0% (FSRT)
Grade 4–5: None; both modalities well tolerated
Conclusions
LINAC SRS and FSRT achieved equivalent 5-yr local control (97.5%) for vestibular schwannoma. Hearing preservation comparable, numerically favoring FSRT (80% vs 73%); SRS had modestly higher peritumoral edema. Modality selection guided by tumor size and hearing function.
Key Limitations
Retrospective, non-randomized with allocation by tumor size/hearing (selection bias); single-institution; unequal follow-up between arms (longer for SRS).
Clinical Context
Supports both single-fraction SRS and FSRT as effective for VS; FSRT often preferred for larger tumors or when hearing preservation is prioritized.