My Dad was diagnosed with stage IV NSCLC Adenocarcinoma back in Dec 2017. He has a couple lymph nodes metastasis and a small metastasis in his liver. He went through 4 cycles of chemo (Pemetrexed+Carboplatin+Bevacizumab) and now the tumor has gone down from 39*29mm to 32*21mm, lymph nodes metastasis seems to be gone and liver one is smaller. Now the onc recommended adding local therapy plus maintenance therapy, and we're struggling to make decisions about if we should go with SBRT (CyberKnife) or conventional RT. They both have pros and cons obviously. And my concern is if we go with SBRT, the lymph nodes might not be treated as what conventional RT would do (although some onc said that if the metastasis is not there for now, no need to treat it). Also, I have heard that there might be possibility that after SBRT treatment you could not use conventional RT in the future, is that true? Anyone has any suggestions regarding the pros/cons as for which treatment to go with? Thank you in advance.