My husband also has stage 4 colon cancer that spread to his liver and lungs. It is over 8 years now. Most of the reply’s , I see, have given you some great advice. My suggestion here is for your hubby. I did not see any mention of cyber knife ( very pinpointed radiation) . My husband has had this done on MANY of the tumors in his lungs (both lungs). Cyber knife has worked every time. The nodules get zapped with the radiation and then are gone. Not to say other new ones don’t appear but the ones he had radiated are gone. Maybe you can look into this for your hubby. We live near Philadelphia and use Philadelphia Cyber Knife. The doctor is Dr. Lanciano. She has kept my husband alive for many years now. Each person has circumstances related to their specific condition, but this might be an avenue for your hubby.