How do you predict the likelihood of radiotherapy causing lung re-expansion in a patient with advanced or metastatic NSCLC and complete lung collapse due to obstructive tumor?

This is a tough question! In situations where there is bronchial obstruction from tumor and lung collapse beyond the lesion, we are often asked to provide palliative irradiation. In those situations, I tend to think about two principles; how long has the distal lung been collapsed, and can intervent...