Would you use SBRT to treat a >5cm NSCLC with chest wall invasion in a medically inoperable patient?

This is a very relevant and interesting question as the patterns of practice and indications for lung SBRT continue to evolve. It also fits in nicely with two recent retrospective reviews we conducted at the Cleveland Clinic using our 10-year old lung SBRT data registry. Addressing the first component of the question, i.e., size and tumors >5 cm, our publication addressing this issue just came out recently in the Red Journal. Simply put, we have treated a range of "large tumors" [median tumor size 5.6 cm (range: 5.1-10 cm)] and as stated in our conclusion: "Lung SBRT for medically inoperable node-negative NSCLC with primary tumors larger than 5 cm is safe and provides excellent local control with limited toxicity. The predominant pattern of...

There are also more modestly hypofractionated regimens described which @Dr. First Last alludes too. Those are also an option in this case. The CALGB hypofractionated regimen of 70Gy in 20 fractions has local control rates that were similar to early SBRT experiences. (CALGB 39904 Bogart et al JCO 2010)

The Canadians delivered 60 Gy in 15 fractions (to isocenter) with pretty good results. NCIC BR.25

These are both reasonable options for a larger tumor that may pose a difficulty to plan with SBRT techniques.

Yes I agree, an SBRT dose regimen (higher dose per fraction and a more localized treatment) can bring better results (local control /pain reduction) than a standard conventional fractionation scheme. Dose to the chest wall should be well documented through to avoid chest wall toxicity.