What dose-volume constraint should be used for the normal brain parenchyma in a patient receiving 5-fraction SBRT?
I have seen small amounts of evidence for V4<20cc and V14<7cc, but overall it seems like there is little published on this issue.
Answer from: Radiation Oncologist at Community Practice
Agree with @Tony J. Wang. Prioritize target and aim for V12 < 10 cc if possible. If not, don’t sweat as the UK consortium and AAPM TG 101, though older, did not have a 5 fxn SRS constraint for normal brain. Should always try to aim for as low as possible though.
If you want a metric to mak...
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Radiation Oncologist at Vanderbilt-Ingram Cancer Center Just to clarify, it was 4Gy per fraction, for a 5 ...
Answer from: Radiation Oncologist at Academic Institution
We do not have established thresholds for V12-V16 for fractionated SRS and adverse events especially limiting dose evaluation to the "normal" brain.We all need to remember, that the optimal models for estimating toxicity post-SRS include the target volume. YOUR TARGET IS YOUR TOXICITY. So first clin...
Answer from: Radiation Oncologist at Community Practice
This is tough, because most of the literature is based upon single fraction SRS for 1-3 lesions. There are no one criteria for brain doses for multi-session treatments as stated above. Tumor coverage is most paramount, and I agree with the need to respect the adjacent structure doses and to optimize...
Answer from: Radiation Oncologist at Academic Institution
I don't have a hard dose-volume constraint for normal brain parenchyma. Depending on the case (brain mets vs benign brain tumors) I would prioritize target coverage, selectivity and gradient/conformity index. The more likely I'm able to keep my isodoses tight the less spillage into normal brain pare...
Answer from: Radiation Oncologist at Community Practice
After the publication of these two articles, are people using these for V25 and V30 for brain? What if unable to meet constraint?BrainV25 > 16 cm3 or BrainV30 > 10 cm3 Andruska et al., PMID 33310010.Faruqi et al., PMID 31928848.
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Radiation Oncologist at Vanderbilt-Ingram Cancer Center Those are reasonable constraints to shoot for, as ...
Radiation Oncologist at Karmanos Cancer Institute - McLaren Proton Therapy Center Thanks Dr. @Christine N. Chang-Halpenny, those are...
Radiation Oncologist at SSM Cancer Center/St Louis CyberKnife Can anyone please clarify if Andruska et al., PMID...
Radiation Oncologist at Vanderbilt-Ingram Cancer Center Andruska paper above used 'uninvolved brain' for t...
Just to clarify, it was 4Gy per fraction, for a 5 ...