Don't really know what to do but can offer some info on whats happend since we found out my mom has stage 4 lung cancer. She had back problems and trouble breathing at 1st. Then she couldn't walk and needed a walker. She was getting radition treatments to her stomach area. Then a few weeks late she got a mri and found out there was tumors in the brain. She then got a small chemo treatment and radiation to the brain. She had a bad reaction to chemo. She lost her appitie and then couldn't move at all anymore. Now she can't talk and her body is giving up. My best advice is try to spend as much time with him as possible and make sure he has a appitie and keeps his wieght up and is comfortable and is taking his meds. It's a tough disease and its tough on the person and family.