Keratoacanthoma

A type of harmless skin nodule that commonly occurs in elderly people, most often on the face or arm. The cause is unknown, but many years of exposure to strong sunlight or long-term use of immunosuppressant drugs may be factors. Initially, the nodule resembles a small wart, but it grows to 1–2cm across in about 8 weeks. Although the nodule usually disappears gradually after this, surgical removal is often recommended to prevent scarring.

 

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