What are congenital nevi?

Also known as: congenital moles, congenital melanocytic nevus

Congenital nevus/i (plural) is the term for a single small to medium sized solitary, flat, or raised tan/dark mole or birthmark that develops from proliferation of pigmented cells. These pigmented cells, known as melanocytes, are present on or in the skin of a baby at birth or within a year or two thereafter.

There is a small risk that these may go on to becoming cancerous. A rare form of congenital mole is the large or giant melanocytic nevus which may be small at birth but grow in size as the child grows. These moles have a greater risk of becoming malignant as cancer called melanoma.

A syndrome called Neurocutaneous melanosis is the presence of small or giant congenital melanocytic nevi on the skin plus melanocytic tumors in the coverings of the brain and spinal cord.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: 1/29/2019 3:21:13 PM

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