Summary
This phase IIb trial tests whether metformin works in preventing oral cancer in patients with oral leukoplakia (white patches) or erythroplakia (red patches). Metformin is in a class of drugs called biguanides. Metformin helps to control the amount of glucose (sugar) in the blood. It decreases the amount of glucose patients absorb from food and the amount of glucose made by the liver. Metformin also increases the body's response to insulin, a natural substance that controls the amount of glucose in the blood. This trial may help researchers determine if metformin can stop changes in the mouth that are related to pre-cancer growths in the mouth.