The following link will take you to an article that I ran across this article several months ago. It talks, very directly, about the function of chemotherapy in the treatment of stage IV cancers versus the perceptions of the people who undergo that treatment. I find this very real disconnect highly disturbing. I'm not sure if there's bad communication between doctors and their patients, if popular culture has something to do with how patients think about their the possible effectiveness of their treatment, or if it's merely a way that people cope with being told that they will die sooner than they originally expected. Whatever it is, it seems to show that people aren't necessarily grounded in the reality of their situation.
Ultimately, it is also about death, which some people find off-putting, so read at your own risk: