My dad is in the same situation. He was diagnosed in April with metastatic lung cancer and underwent 2 lots of chemo/immuno but this hospitalised him 3 times with infections and kidney failure. We were told the treatment wasn’t working and the risk outweighed the benefit. We pushed for another chance out of desperation to which the oncologist reluctantly agreed. In the meantime whilst waiting for the treatment, he developed paralysis of his left arm. A scan sadly showed progression to the brain. Fortunately, they have identified a gene mutation that changes the whole treatment and he has started this today with a view to getting this awful disease under some sort of control. He is on a tablet form of chemo. Please ask if they have done genetic testing on his cancer as this has turned my dad’s whole treatment/prognosis around. I don’t know how it works but it’s taken from April to now for this to be found. It was almost too late. 

Thank you I will ask x