What dose, constraints, and technical parameters would you use for a SIB FSRT plan for a large brain metastasis resection cavity with rapid interval tumor growth along periphery of the resection cavity?  

Depending on the location of the tumor and the size of the nodular enhancing part at the periphery of the resection cavity, I would use a SIB/FSRT plan delivering 24 Gy in 3 fractions to the entire wall of the cavity while delivering 27 Gy in 3 factions simultaneously to the nodular enhancing part.

I would likely recommend discussing the possibility of a re-resection with a neurosurgeon as the initial step. If re-resection is not a viable option, my inclination would be to consider a 5-fraction regimen (30 Gy delivered in 5 daily fractions). It's worth noting that there are limited data suppor...