Ulcers
An ulcer is a crater-like sore on the skin or mucous membrane. Ulcers form when the top layers of skin or tissue have been removed. They can occur in the mouth, stomach, and other parts of the body.
Mucous membrane
Mucosa is moist tissue that lines certain parts of the inside of your body. It is in your: NoseMouthLungsDigestive tractUrinary and genital tracts G...

Causes
Ulcers can be caused by inflammation, trauma, or infection. Some ulcers may be caused by a cancer.
Cancer
Cancer is the uncontrolled growth of abnormal cells in the body. Cancerous cells are also called malignant cells.
Read Article Now Book Mark ArticleReviewed By
Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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