Is there evidence to support the use of definitive CRT in patients with NSCLC in separate ipsilateral lobes and mediastinal lymph node involvement?   

Challenging question. I am not aware of any level I evidence to answer this. In the absence of randomized data, I would allow common sense to prevail. Staging of this went from M1 to T4 from AJCC 6th edition to 7th edition mostly because these patients do better by survival then the traditional stag...

I agree, management depends on many factors including: location of ipsilateral nodule, if biopsy has been performed and nodule showed same histology confirming it is not a separate primary, extent of N status, and whether including it in the same radiation field would significantly increase toxicity...