Is there a chest wall constraint you typically use for 60 Gy in 15 fraction NSCLC treatment?  

We generally keep chest wall Dmax <110% and keep as much 105% out of the chest wall as possible, with a very low-priority goal of V4000 cGy <30 cc. I am definitely not strict about this in most cases, especially the volumetric goal.

Just found a paper on this topic: "Incidence and predictors of chest wall toxicity after high-dose radiation therapy in 15 fractions", Swanick et al., PMID 27637136. They found that with CW pain, incidence with V40 <150 cm3 vs =>150 cm3 was significant (11% vs 26%). 

This paper by Li et al., PMID 25108807 has constraints and toxicity outcomes for 70 Gy in 10 fractions, which I have sometimes extrapolated from when the volume is large for 60/15 cases. In general, I have not had many issues with chest wall pain after 60/15 even when exceeding these. I agree with D...