firstly, most likely it is not cancer but rather a "mucocele", which is basically a saliva filled bubble. they are common. If you get another one, go to your dentist and have him or her look at it if not for anything else than to reassure you. secondly, contemplate how scared you are about cancer, and think about this--- smoking kills people. it gives people lung cancer. when you are given a diagnosis of lung cancer, you're most often dead within a few years, if not months.