Mouth cancer, also commonly referred to as oral cancer, is a serious type of cancer that affects the tissues of the mouth, including the lips, tongue, inner cheeks, gums, and the lower part of the mouth. It falls under the broader category of head and neck cancers, as it involves areas that are closely connected anatomically and functionally. Mouth cancer is considered a highly aggressive condition if not detected early, and treatment often involves a combination of surgery, radiation, and sometimes chemotherapy.