For ultracentral lung cancer abutting the heart, what dose constraints would you use for the heart and bronchus if using 10 fraction ultrahypofractionation?

The dose deviation from Timmerman for the heart is 60 Gy in 10 fractions. Now that they are published, I'd utilize the SUNSET constraints. Patients received 60 Gy/8 fractions (rather than the 10 fraction regimens questioned here) but the best data we have to extrapolate and use constraints that are safe in 8 fractions should be even more conservative for 10. See comprehensive list from SUNSET below:

Spinal Cord D0.1cc < 34 Gy
Brachial Plexus D0.1cc < 39 Gy
Esophagus D0.035cc < 45 Gy
Esophagus V40 < ...

For "intra-central lung cancer” that closes or abuts the heart or bronchial tree, we could potentially treat with 70 Gy in 10 fractions with SIB GTV to 80 Gy. We typically keep heart Dmax<60 Gy, V50 Gy < 1cc; bronchial tree Dmax <60 Gy, and V50 < 1 cc. We understand this is a conservative dose-volume constraint and need to balance the individual’s efficacy and toxicities case by case.