A sore or discolored tissue in the mouth are two common visible manifestations of mouth cancer, which is also known as oral cancer, according to WebMD. Pictures of oral cancer can be viewed on Healthline.com and WebMD.com.
Sores that are indicative of oral cancer may have a similar appearance to cold sores or canker sores, but can be distinguished from them by not going away and by growing larger as time passes. It is also common to see red and white patches of tissue in pictures of oral cancer. Healthline states that sores and discolored tissue in the mouth that persist for more than two weeks should be examined by a doctor.