When it is caught early, oral cancer is much easier for doctors to treat. You can take an active role in detecting oral cancer early, should it occur, by conducting a self-exam at least once a month. Using a bright light and a mirror, look and feel your lips and front of your gums. Tilt your head back and look at and feel the roof of your mouth. Pull your checks out to view the inside of your mouth, the lining of your cheeks, and the back gums. Pull out your tongue and look at all surfaces; examine the floor of your mouth. Look at the back of your throat. Feel for lumps or enlarged lymph nodes in both sides of your neck and under your lower jaw.