A 68-year-old black man who has smoked for at least 50 years…

A 68-year-old black man who has smoked for at least 50 years reports that lately he feels as though food is getting stuck in his throat. At first this was a problem just with dry food, but now his morning oatmeal is getting “stuck.” On questioning, he reports drinking at least 3 alcoholic beverages nearly every day. Which is most likely his problem?