HELP!! my mom never goes to the doctor, and she's going next week?

okay, so I know my mom has smoked for basically my whole life and she probably did before she had me too. she doesn't exactly know that me and my three sisters know about it, but that isn't really the point. about 6 months ago she started coughing A LOT and she has been coughing up lots of flem or whatever you call it. she never really goes to the doctor, she just refuses to, and when she did in the past, stupidly she lied to the doctor about her smoking. but, a couple of days ago she decided she was going to go see a doctor about her coughing and i really want to discuss with her if she thinks it might me lung cancer or something like that? i dont know, but im really worried! help please!