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Noncancerous, Precancerous and Cancerous Tumors

Picture of Congenital Nevi

Picture of Congenital Nevi

Congenital nevi are moles that are present at birth. These birthmarks have a slightly increased risk of becoming skin cancer depending on their size. Larger congenital nevi have a greater risk of developing skin cancer than do smaller congenital nevi. All congenital nevi should be examined by a health care provider and any change in the birthmark should be reported. If a dermatologist believes a mole needs to be evaluated further or removed entirely, he or she will either remove the entire mole, or first take just a small tissue sample of the mole to examine thin sections of the tissue under a microscope (a biopsy). This is a simple procedure. (If the dermatologist thinks the mole might be cancerous, cutting through the mole will not cause the cancer to spread.)

Image Source: Fitzpatrick's Color Atlas & Synopsis of Clinical Dermatology Klaus Wolff, Richard Allen Johnson, Dick Suurmond Copyright 2005, 2001, 1997, 1993 by The McGraw-Hill Companies. All Rights reserved.

Text Reference: National Organization for Rare Diseases: “Giant Congenital Melanocystic Nevus”