We’ve all heard the rumors—there’s a cure for cancer but the “powers-that-be” won’t make it public; or a positive attitude is all you need to beat cancer—and it’s hard to tease out fact from fiction. As an oncologist, I hear patients’ concerns about these kinds of rumors all the time. This guide provides some preliminary, accessible resources that give useful information on what’s scientific fact, what’s science fiction and what remains unknown to science.