*Exact cause is unknown, thought to be caused by an unidentified gene defect related to male hormones
*Consists of a large, single-sided brown pigmentation, darkening with time
Becker's Nevus is a condition in which a birthmark develops in adolescents. The birthmark is generally brown and quite large, usually forming on the shoulders, back or upper chest, and sometimes covering over half of these areas. After puberty, the nevus will become dark and grow thick, coarse hair. Occasionally, Acne may form within the birthmark. Very rarely, much like other forms of birthmark, it may cause or be related to abnormalities in underlying tissues. This condition is known as Becker's Naevus Syndrome, and may include overgrowth of smooth muscle tissue, under-development of underlying bone or muscle structures, or over-development of other tissues.
Becker's nevus affects almost exclusively males. The birthmark itself is caused by excessive growth of the upper layer of the skin, pigment cells, and hair follicles. While the exact cause isn't known, Becker's nevus is thought to be triggered by a gene defect related to the circulation of male hormones.
Differential Diagnosis (Other conditions with similar appearance)
*Diagnosis based on skin appearance
*Skin biopsy may be performed to rule out other conditions
Becker's Nevus is diagnosed based on appearance and in conjunction with family history and associated symptoms, if extant. Health care professionals may perform a Skin biopsy to rule out other conditions.
*No effective treatment
*Goal of treatment is to control certain symptoms
There is no truly effective treatment for the pigmentation resulting from Becker's nevus. It is recommended that affected persons keep the area out of direct sunlight, as sun exposure can darken the area. While the pigmentation can be lessened with pigment laser treatments, these treatments are not entirely effective and can, in fact, make the pigmentation worse in some cases.
The hair growth associated with Becker's Nevus can be reduced or eliminated by hair removal laser or electrolysis treatments. Associated Acne can be treated with standard Acne treatments, including the use of Isotretinoin in severe cases.