What criteria do you use to decide between 1 fraction vs multi-fraction (e.g. 5 fractions) for WHO 1 meningiomas?

This is an important, frequently encountered, and clinically relevant question. I will address it as posed, but intend to emphasize that, although stereotactic radiosurgery (SRS) is an important therapeutic option for WHO grade I meningioma patients requiring RT, it does not displace external beam RT with standard 1.8 to 2.0 Gy fractionation from our armamentarium. With that caveat, let's focus on the question.

SRS is has been most effective for patients with a meningioma less than 2.5 to 3 cm in...