Top Line: How many brain mets is too many to treat with radiosurgery?
The Study: Ohio State says there’s no such thing. Here is a look at outcomes for 118 patients receiving radiosurgery for ≥15 brain mets between 2014-2022. The median was 20 and the range—no, we are not about to make a typo—was 15 to 94. Median total tumor volume per patient was 7 cc (interquartile range 2-16 cc). The technique was single-iso VMAT with HyperArc planning when available. One-third of patients (n=39) had prior radiosurgery, whole brain radiation or both, and the most common prescription was 27 Gy to GTVs and 24 Gy to PTVs with a 2-mm margin in 3 fractions (82%). The primary endpoint of grade 3 radionecrosis occurred in 4 patients, all alive at one year. While the cynic might say this low rate is in no small part due to a median survival <6 months, radionecrosis was clearly not a red flag limitation to this approach. Only 3 patients experienced local failure and roughly half (n=62) distant failure of whom 24 received salvage whole brain radiation. Longitudinal patient-reported cognitive function questionnaires were available on 31 patients at 6 months at which point the majority felt stable (n = 20) or improved (n = 5).
TBL: Concerns surrounding safety and efficacy are not good reasons to withhold radiosurgery for a relatively high number of brain mets; the more important nuance is optimally selecting patients who will live long enough to benefit. | Upadhyay, Adv Radiat Oncol 2024
The Study: Ohio State says there’s no such thing. Here is a look at outcomes for 118 patients receiving radiosurgery for ≥15 brain mets between 2014-2022. The median was 20 and the range—no, we are not about to make a typo—was 15 to 94. Median total tumor volume per patient was 7 cc (interquartile range 2-16 cc). The technique was single-iso VMAT with HyperArc planning when available. One-third of patients (n=39) had prior radiosurgery, whole brain radiation or both, and the most common prescription was 27 Gy to GTVs and 24 Gy to PTVs with a 2-mm margin in 3 fractions (82%). The primary endpoint of grade 3 radionecrosis occurred in 4 patients, all alive at one year. While the cynic might say this low rate is in no small part due to a median survival <6 months, radionecrosis was clearly not a red flag limitation to this approach. Only 3 patients experienced local failure and roughly half (n=62) distant failure of whom 24 received salvage whole brain radiation. Longitudinal patient-reported cognitive function questionnaires were available on 31 patients at 6 months at which point the majority felt stable (n = 20) or improved (n = 5).
TBL: Concerns surrounding safety and efficacy are not good reasons to withhold radiosurgery for a relatively high number of brain mets; the more important nuance is optimally selecting patients who will live long enough to benefit. | Upadhyay, Adv Radiat Oncol 2024