People try to arrive at an understand by putting things in categories. Aha she/he smoked ..... therefore it can be "understood" why this person gets cancer. Never mind that it is possible that smoking might not have had anything to do with it....
However, if you smoked and end up here is is quite likely that this activity caused the cancer. It is what it is and smoking is the most preventable cause for cancer. There is no point in glossing over this.

I had my last cigarette the day before the glossectomy (..... exactly!!).

M