I'd developed irritation behind my upper teeth, and as it wouldn't go away even when I stopped smoking for 2 weeks (which hurt a lot more than the irritation!), I went to my dentist to have it checked out. I like him and he's worth a good listen. He examined me in about 15 seconds, took a step back and went into a 10 minute monolog about the dangers of tobacco; he saw no reason to biopsy the tissue. A friend of his who smoked died from oral cancer, and he told me about him, again, and he cited other case histories. He also said that tobacco use is a cause that accretes and that it may trigger at that next smoke you have, and you never know when that will be.
I thought about it and decided that if I get cancer, I get it, but as there are few things in my life that are meaningful, and smoking is, I'll not put it down.
But the experience was sobering. I wasn't upset that he said so much but rather admired it, his valiant effort to stave off what he perceives as my impending disaster.