What is your preferred fSRS dose/fractionation for large brain metastases?
How does the presence of prior WBRT alter your treatment plan?
Answer from: Radiation Oncologist at Community Practice
Noting that "large" can be reasonably defined (and is variably reported) by maximal tumor diameter >2 to >3cm or volume >4 to >15cc, based upon poor LC for current dose single-fx recommendations at these size/volumes (1y LC <50% as per historic RTOG 90-05), as well as subsequent repor...
Answer from: Radiation Oncologist at Academic Institution
Answer from Rupesh Kotecha, MD, and Minesh Mehta MD, Miami Cancer Institute:For intact brain metastasis, our current prescription approach is based on the maximum tumor diameter (Kotecha R, Mehta M, IJROBP 2019):a. For lesions < 2.0 cm in size: 24 Gy in 1 fractionb. For lesions 2.1 &n...
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Radiation Oncologist at Vasek Polak Radiation Oncology
Can you clarify what you mean by the "a 4-week (or...
Can you clarify what you mean by the "a 4-week (or...
Answer from: Radiation Oncologist at Academic Institution
In contrast to dosing for single-fraction SRS, there is not consensus for the optimal dosing for multi-fraction SRT. The two most common dose regimens are 9 Gy x 3 or 6 Gy x 5. Retrospective data does seem to indicate a dose-response relationship. For example, the University of Alabama showed better...
Answer from: Radiation Oncologist at Academic Institution
This is relatively rare, as most brain mets can be treated with 1-2 sessions to 20 or 25 Gy. With proton fSRS, I have used 3 x 9 Gy as well, and occasionally 4 x 6 Gy for posterior fossa/brain stem metastases, prescribed to the 80% isodose line, and applied without additional range uncertainty for p...
Is there a cavity size where you would reduce the ...
Our experience may be a bit different. We have tre...