I first began to notice the dangerous power of this word when I was working in cancer research. To a cancer researcher, cancer is a thing one deals with all day long, but at a very safe emotional distance. You're used to cancer cells; you study them all the time. You spend quite a lot of time carefully raising them in dishes. You give excited talks about how they work. Still, it's hard not to notice that when you tell a stranger on the street what your research is about, there's this little intake of breath.
And then I grew a bit older, and some friends and I lost relatives to cancer, so we got the chance to actually experience the process from the patient's point of view. (An opportunity which, fortunately, many young people don't get.) And I gradually realized, at a gut level, what all the fuss was about: Cancer is really awful. Dying of it is awful, and not dying of it is also pretty damned awful, because the treatments are painful, often damaging, often disfiguring, and dreadfully uncertain.
Don't use the word unless you mean it. And you probably don't mean it.