Kiểm tra miệng thường xuyên. Tìm vết loét nhỏ màu trắng. Để ý vết loét hay mảng màu đỏ. Sờ tìm khối u và mảng nhám. Đừng bỏ qua dấu hiệu đau nhức.

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Most cancers of the mouth and throat cause some identifiable signs or symptoms during their early stages, but not all do. In some cases, cancers don't cause symptoms until they’ve reached an advanced stage. Regardless, doctors and dentists recommend that in addition to regular checkups, you should carefully look at your mouth in a mirror at least once a month to check for any abnormal signs.  Oral cancers can grow virtually anywhere in your mouth and throat, including the lips, gums, tongue, hard palate, soft palate, tonsils, and insides of the cheeks. Teeth are the only parts that can't develop cancer. Consider buying, or borrowing from your dentist, a small dental mirror in order to help you examine your mouth more thoroughly. Brush your teeth and floss before examining your mouth. If your gums normally bleed after brushing or flossing, rinse with some warm salt water and wait a few minutes before examining. Check all around your mouth for small white sores or lesions, which are called leukoplakia by doctors. Leukoplakia are common precursors to oral cancers, but they are often misdiagnosed as canker sores or other small ulcers caused by abrasions or minor trauma. Leukoplakia can also be mistaken for bacterial infections of the gums and tonsils, as well as Candida yeast overgrowth in the mouth (called thrush).  Although canker sores and other ulcers are usually very painful, leukoplakia aren't typically, unless they're in advanced stages. Cankers are most common on the inner lips, cheeks and sides of the tongue, whereas leukoplakia can be anywhere in the mouth. With good hygiene, canker sores and other small abrasions and cuts usually heal within a week or so. In contrast, leukoplakia don't go away and often become larger and more painful with time. While checking the inside of your mouth and back of your throat, watch out for small red sores or patches. Red sores (lesions) are called erythroplakia by doctors, and although less common than leukoplakia in the mouth, they have a much greater potential for...