CyberKnife for lung cancer

My mom(70yo)was diagnosed stage 3 lung cancer,tumour 24*37mm in upper  lobe of the left lung,mets in lymph nodes of the mediastinum 30*25,10mm.,adenous cr.cells were found out on punction. She had 4 chemo, after 1and 2 the tumour shrunk, after 3-4 it had stabilized.At the moment she is preparing for RT(traditional).Having visited a new cyber clinic I was recomended(not insisted on) to have treatment on cyberknife for the turmour only, mets should be radiated with a common way (linac, cobalt) because of them inaccessible location for CK.RT Radiologist  was sceptical of the efficiency of CK and advised to have  a traditional RT treatment. Is any sence to try CK in my case?Thank you so much.