What dose-volume constraint should be used for the normal brain parenchyma in a patient receiving 5-fraction SBRT?

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...

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...

Agree with @Dr. First Last. 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 make you fe...

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...

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.