What is the quickest palliative regimen you have tried for obstructing lesions in the lung in patients with stage IV disease?  

I routinely use 1 or 2 fraction palliative regimens, and in my opinion, this is something that we should be considering more frequently. This has been the subject of dozens of randomized controlled trials, and meta-analyses by the Cochrane group. There is consistently no difference in symptom relief...

I agree completely with @Roy H. Decker. I may use 17 Gy in 2 fractions separated by a week in some circumstances, toward the end of life or when patients require monitoring to receive treatment [e.g. ICU].