Hi. My father in law had lung cancer and had an extensive surgery in which they had to remove half of one lung. They weren't sure if they were able to get all of the cancer due to complications during the surgery. he had a severe lung infection and they had a mess to deal with once they were in there. He went on to get chemo treatments but never fully completed them because he could no longer handle the side effects. Its been 4 months and we have noticed a change in him in the last month. It started with just forgetting words but has quickly gotten worse. He talks a lot. He is using wrong words for things or forgetting them all together. He is slurring when he talks and constantly seems to be struggling to get his words out. He is asking unusual questions and talking about things that have nothing to do with the conversation. This is all new and seems to be getting worse by the week. He refuses to go to the doctor. I am concerned the cancer has gone into the brain or that he has had a mini stroke. He has diabietes and high blood pressure.