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Genetic and Rare Diseases Information Center (GARD)

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Becker's nevus

Other Names for this Disease
  • Becker melanosis
  • Becker naevus
  • Becker nevus
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What are the signs and symptoms of Becker's nevus?

A Becker's nevus typically begins to develop during childhood or adolescence on the shoulder or upper trunk, although it may develop on other areas of the body.[1] Pigmentation may be subtle at first, but the nevus typically expands during the first several years.[2] The resulting birthmark is usually large, brown, and on only one side of the body. Sometimes it may cover over half of the upper back or chest. After puberty, the nevus often darkens and becomes hairier than the surrounding skin (hypertrichosis). In some individuals, acne may develop within the nevus.[1]

Rarely, there may be abnormalities of underlying tissues associated with the nevus, such as ipsilateral breast hypoplasia (underdevelopment of the breast on the same side of the body as the nevus). When this occurs, it is sometimes known as Becker nevus syndrome, a type of epidermal nevus syndrome.[1] In addition to the nevus, individuals with Becker nevus syndrome may have various skin-related (cutaneous), muscular or skeletal abnormalities.[1][3]
Last updated: 4/25/2012

  1. Vanessa Ngan. Becker naevus. DermNet NZ. June 29, 2011; Accessed 4/20/2012.
  2. Jason K Rivers. Becker Melanosis. Medscape Reference. April 3, 2012; Accessed 4/23/2012.
  3. Wilson H. Y. Lo. Becker Nevus Syndrome. OMIM. May 4, 2000; Accessed 4/23/2012.