- Cancer of the mouth and throat is one of the most common cancers in Taiwan. This cancer develops over several years, beginning as white or red patches in the mouth or throat that become growths. It can also cause a condition that leads to rigidity of the cheeks. The growths can be identified when a doctor looks into a person s mouth. It is currently not clear why some people with abnormal growths progress to cancer while others do not. Researchers want to better understand why some patients with early abnormal growths get late abnormal growths. They also want to understand why some people get abnormal growths again, even after they receive treatment.