Congenital Nevi Clinical Presentation

Updated: Mar 17, 2023
  • Author: Robert A Schwartz, MD, MPH; Chief Editor: Dirk M Elston, MD  more...
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Presentation

Complications

Patients with giant congenital melanocytic nevi have an increased risk of developing melanoma (as high as 5-7% by age 60 y). The lifetime risk of malignant transformation associated with smaller nevi is surely smaller than that for giant nevi but is unknown at this time.

Large congenital melanocytic nevi are associated with an increased risk for developing cutaneous melanoma, leptomeningeal melanoma, neurocutaneous melanocytosis, malformations of the brain, and, rarely, rhabdomyosarcoma and liposarcoma. The risk of developing malignancy in association with congenital melanocytic nevi is dependent on the size of the nevus; the risk of developing neurocutaneous melanocytosis correlates best with the number of satellite nevi. [34]

Congenital melanocytic nevi may be linked with neurologic melanocytic (neuromelanocytosis, melanoma) and nonmelanocytic (syringomyelia, related hydrocephalus, ependymoma, meningioma, astrocytoma, choroid plexus papilloma, pineal germinoma, and malformations such as Dandy‐Walker and Arnold‐Chiari malformations) findings and possibly hypophosphatemic rickets. [35]