is mainly of two types. Small cell lung cancer and non-small cell lung cancer. I do not know what is the diagnosis of your father. If his liver
has already been involved then it is a case of M1b lung cancer that is stage IV disease. In this case chemotherapy
is the main treatment option but on good response with chemotherapy maintanance with Oral targetted therapy is also an option. For this treatment EGFR status to be known if it is a non small cell lung cancer. Biological therapy is another options which will be selected depending on histopathology. Consult with your oncologist
. Take care.