Yes. I too unfortunately am a smoker. Smokers have been blamed from everything from the boil on one's butt to the mystery of ALL diseases. Other things in our environment can cause cancer as well (they know little about cancer after all these years) and some medications such as HRT can cause breast cancer as well. In Canada there was a news broadcast just about that very thing.
Still, smoking is not good for anyone and hopefully I hope to quit if I can. It's tough and I may not win, but I have to try.
There are many tumors in the body not related to cancer, but please, go and see your doctor and get it checked out. Letting it go gives you plenty of worry (probably needless) and if it should be cancer you want to catch it early.