What dose/fractionation would you consider for salvage re-irradiation of a vestibular schwannoma after fractionated stereotactic radiation, >4 years later?

In a patient experiencing true progression of vestibular schwannoma following prior 25 Gy in 5 fractions, 4 years earlier, which of the following options would you offer?

• 1. Salvage SRS, full dose, 12.5 Gy
• 2. Salvage SRS, reduced dose, 10-11 Gy
• 3. Salvage FSRT, full dose, 25 Gy in 5 fractions
• 4. Salvage FSRT, reduced dose, 20 Gy in 5 fractions
• 5. Conventionally fractionated 45 Gy in 25 fractions, using advanced RT or proton techniques
• 6. Surgical resection