Not really enough for you to claim you "know all about it." Since cancer is the number on killer of folks under 70, a great number of people have had similar experiences from the patient viewpoint I can claim a couple of relatives who died from it too, but I actually learned more about it in terms of therapy, prognoses, and staging from a course in oncology I took years ago, but I'd never claim to know all about it.
I know enough to know that Stage IV is unrelieved bad news, and that she'll most likely be dead in two years or less, and that if Edwards chooses to pursue his presidential ambitions instead of spending time with her I'd judge him to be a jerk (kind of like Newt, whom I know is a jerk).