Continually Updated Clinical Reference
 
 
  All Sources     eMedicine     Medscape     Drug Reference     MEDLINE
 
eMedicine - Becker Melanosis : Article by

Quick Find
Authors & Editors
Introduction
Clinical
Differentials
Workup
Treatment
Follow-up
Miscellaneous
Multimedia
References

Related Articles
Albright Syndrome




Patient Education
Click here for patient education.


AUTHOR AND EDITOR INFORMATION

Section 1 of 10 Click here to go to the next section in this topic  

Author: Jason K Rivers, MD, FRCP(C), Clinical Professor, Department of Dermatology and Skin Science, University of British Columbia, Canada; Consulting Staff, Pacific Dermaesthetics

Jason K Rivers is a member of the following medical societies: American Academy of Dermatology, American Society for Dermatologic Surgery, American Society for Laser Medicine and Surgery, British Columbia Medical Association, Canadian Dermatology Association, Canadian Medical Association, Pacific Dermatologic Association, Royal College of Physicians and Surgeons of Canada, and Women's Dermatologic Society

Coauthor(s): Marni C Wiseman, MD, FRCPC, Assistant Professor, University of Manitoba, CancerCare Manitoba

Editors: Günter Burg, MD, Professor and Chairman Emeritus, Department of Dermatology, University of Zürich School of Medicine, Switzerland; Michael J Wells, MD, Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center; Lester F Libow, MD, Dermatopathologist, South Texas Dermatopathology Laboratory; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center

Author and Editor Disclosure

Synonyms and related keywords: Becker's nevus, Becker nevus, Becker's pigmented hairy nevus, Becker pigmented hairy nevus, nevus spilus tardus, pigmented hairy epidermal nevus

INTRODUCTION

Section 2 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Background

In 1948, S. William Becker described 2 young men with acquired melanosis and hypertrichosis in a unilateral distribution.1 Since then, this condition has been termed Becker nevus.

Pathophysiology

The pathogenesis of Becker nevus remains uncertain.

Androgens may play a role as evidenced by its peripubertal development, male preponderance, hypertrichosis, occasional development of acneform lesions within the patch, and rare association with accessory scrotum in the genital region. In addition, a significant increase in the number of androgen receptors in lesional skin has been reported.

Frequency

International

A study of 19,302 men aged 17-26 years revealed a prevalence of 0.52%.

Sex

Males are affected more often than females.

Age

Although Becker nevus usually is a sporadic condition that manifests in the peripubertal period, both congenital and familial cases2 have been described.


CLINICAL

Section 3 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

History

  • The earliest finding of Becker nevus is an asymptomatic irregular tan-to-brown patch, most commonly located over the shoulder, upper chest, or back (Media File 1).
    • Pigmentation may be subtle, and onset most commonly occurs in the peripubertal period.
    • The patch expands during the first several years as new irregular pigmented macules and patches develop at the periphery and coalesce with the larger patch.
    • This expansion results in a geographic configuration that may cover a large area.
  • Several months to years after the appearance of pigmentation, thick brown-to-black hairs develop both within and in close proximity to the patch. Hair density is highly variable and occasionally, hypertrichosis does not occur.
  • The central area in the patch may thicken, and acne vulgaris may develop.
  • Once present, the patch remains indefinitely, although minimal pigmentary fading may occur in adulthood.
  • Associated findings
    • Occasionally, Becker nevus may be associated with smooth muscle hamartoma. Rarely, hypoplasia of underlying structures, such as unilateral breast hypoplasia, has been reported.
    • Other associations seen with Becker nevus include unilateral or ipsilateral pectoralis major aplasia, ipsilateral limb shortening, ipsilateral foot enlargement, spina bifida, scoliosis, pectus carinatum, localized lipoatrophy,3 congenital adrenal hyperplasia,4 polythelia,5 and accessory scrotum.6
    • Becker nevus is considered a benign process; however, an association with melanoma was discussed in a series of 9 patients in whom both Becker nevus and melanoma developed. In this series, 5 patients developed melanoma on the same body site as the Becker nevus, but in 1 patient only did melanoma develop within the Becker nevus.

Physical

See History.

Causes

See Pathophysiology.


DIFFERENTIALS

Section 4 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Albright Syndrome

Other Problems to be Considered

A Becker nevus on the upper trunk in a peripubertal male is difficult to confuse with other pigmented lesions.

Occasionally, a congenital Becker nevus may simulate congenital melanocytic nevus or nevus spilus, necessitating histologic examination to distinguish between lesions.

A Becker nevus without hypertrichosis may resemble a café au lait patch or postinflammatory hyperpigmentation.


WORKUP

Section 5 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Procedures

Skin biopsy provides histologic diagnosis of Becker nevus and helps distinguish it from other clinical entities.

Histologic Findings

The epidermis demonstrates mild acanthosis and hyperkeratosis with regular elongation of rete ridges (Media File 2).

The basal layer demonstrates hyperpigmentation resulting from increased melanin. Although often normal in number, an increase in the number of basal melanocytes occasionally can be detected.

Ultrastructurally, melanosomes are increased in keratinocytes, and giant melanosomes may be found in both keratinocytes and melanocytes.

Melanophages are present in the superficial dermis. Clinical hypertrichosis correlates with an increased number of morphologically normal follicular units. Almost every case demonstrates at least a slight increase in dermal smooth muscles.

Patches associated with smooth muscle hamartoma demonstrate more pronounced smooth muscle bundles irregularly dispersed within the dermis and unrelated to either hair follicles or vascular channels.


TREATMENT

Section 6 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Surgical Care

Therapeutic intervention for Becker nevus primarily is for cosmetic reasons. Patients present with complaints related to hypertrichosis and/or hyperpigmentation.

  • Q-switched ruby laser (694 nm) has been used with variable success in the treatment of both the hypertrichosis and hyperpigmentation of Becker nevus.7, 8, 9
    • Histopathologic analysis of lesional skin after laser treatment showed selective damage of superficially located melanocytes but a persistence of adnexal melanocytes.
    • Remaining pigment cells may account for the transient improvement noted clinically.
  • A prospective study10 demonstrated the superiority of an Er:YAG laser (n= 11) over a Q-switched Nd:YAG system (n = 11) in the treatment of Becker nevus. Evaluation 2 years after treatment showed that 54% of subjects treated with the Er:YAG laser showed complete clinical clearance, while a clearance of greater than 50% occurred in 100% of the subjects. By comparison, none of the patients who received 3 treatments with the Nd:YAG laser system cleared completely and only one person had marked improvement.


FOLLOW-UP

Section 7 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Patient Education

Advise patients that this is a benign entity and does not require treatment except for cosmetic reasons.


MISCELLANEOUS

Section 8 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Medical/Legal Pitfalls

  • Failure to avoid the use of wide surgical excision, which is unnecessary and can result in unacceptable scars
  • Failure to advise patients that excision of lesions can result in scars more unacceptable in appearance than original lesions
  • Failure to inform patients that laser ablation of lesions may not be possible and that postinflammatory hypopigmentation or hyperpigmentation and/or textural change of treated areas can ensue and can be permanent


MULTIMEDIA

Section 9 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page Click here to go to the next section in this topic  

Media file 1:  Becker nevus of chest wall with associated hypertrichosis. Courtesy of Jason K. Rivers, MD.
Click to see larger pictureClick to see detailView Full Size Image
Media type:  Photo

Media file 2:  Becker nevus demonstrating smooth muscle bundles in the dermis. Courtesy of Jason K. Rivers, MD.
Click to see larger pictureClick to see detailView Full Size Image
Media type:  Photo


REFERENCES

Section 10 of 10 Click here to go to the previous section in this topic Click here to go to the top of this page

  1. Becker SW. Concurrent melanosis and hypertrichosis in a distribution of nevus unius lateris. Arch Dermatol. 1948;60:155-60.
  2. Fretzin DF, Whitney D. Familial Becker's nevus. J Am Acad Dermatol. Mar 1985;12(3):589-90. [Medline].
  3. Van Gerwen HJ, Koopman RJ, Steijlen PM, Happle R. Becker's naevus with localized lipoatrophy and ipsilateral breast hypoplasia. Br J Dermatol. Aug 1993;129(2):213. [Medline].
  4. Lambert JR, Willems P, Abs R, Van Roy B. Becker's nevus associated with chromosomal mosaicism and congenital adrenal hyperplasia. J Am Acad Dermatol. Apr 1994;30(4):655-7. [Medline].
  5. Urbani CE, Betti R. Polythelia within Becker's naevus. Dermatology. 1998;196(2):251-2. [Medline].
  6. Szylit JA, Grossman ME, Luyando Y, Olarte MR, Nagler H. Becker's nevus and an accessory scrotum. A unique occurrence. J Am Acad Dermatol. May 1986;14(5 Pt 2):905-7. [Medline].
  7. Kopera D, Hohenleutner U, Landthaler M. Quality-switched ruby laser treatment of solar lentigines and Becker's nevus: a histopathological and immunohistochemical study. Dermatology. 1997;194(4):338-43. [Medline].
  8. Nelson JS, Applebaum J. Treatment of superficial cutaneous pigmented lesions by melanin-specific selective photothermolysis using the Q-switched ruby laser. Ann Plast Surg. Sep 1992;29(3):231-7. [Medline].
  9. Raulin C, Schönermark MP, Greve B, Werner S. Q-switched ruby laser treatment of tattoos and benign pigmented skin lesions: a critical review. Ann Plast Surg. Nov 1998;41(5):555-65. [Medline].
  10. Trelles MA, Allones I, Moreno-Arias GA, Vélez M. Becker's naevus: a comparative study between erbium: YAG and Q-switched neodymium:YAG; clinical and histopathological findings. Br J Dermatol. Feb 2005;152(2):308-13. [Medline].
  11. Bhawan J, Chang WH. Becker's melanosis: an ultrastructural study. Dermatologica. 1979;159(3):221-30. [Medline].
  12. Burgreen BL, Ackerman AB. Acneform lesions in Becker's nevus. Cutis. May 1978;21(5):617-9. [Medline].
  13. Copeman PW, Jones EW. Pigmented hairy epidermal nevus (Becker). Arch Dermatol. Sep 1965;92(3):249-51. [Medline].
  14. Danarti R, König A, Salhi A, Bittar M, Happle R. Becker's nevus syndrome revisited. J Am Acad Dermatol. Dec 2004;51(6):965-9. [Medline].
  15. Do JE, Kim YJ, Kang HY. Hypohidrosis colocalized with Becker's naevus. Br J Dermatol. Apr 2007;156(4):766-7. [Medline].
  16. Entwisle BR, Nurse DS. Becker's melanosis and hypertrichosis. Australas J Dermatol. Dec 1967;9(2):198-203. [Medline].
  17. Fehr B, Panizzon RG, Schnyder UW. Becker's nevus and malignant melanoma. Dermatologica. 1991;182(2):77-80. [Medline].
  18. Glinick SE, Alper JC, Bogaars H, Brown JA. Becker's melanosis: associated abnormalities. J Am Acad Dermatol. Oct 1983;9(4):509-14. [Medline].
  19. Goldman MP, Fitzpatrick RE. Treatment of benign pigmented cutaneous lesions. Cutan Laser Surg. 1994;106-41.
  20. Nanni CA, Alster TS. Treatment of a Becker's nevus using a 694-nm long-pulsed ruby laser. Dermatol Surg. Sep 1998;24(9):1032-4. [Medline].
  21. Ohtsukam H. Ruby laser treatment of pigmented skin lesions. Jpn J Plast Reconstr Surg. 1992;29:231-7.
  22. Person JR, Longcope C. Becker's nevus: an androgen-mediated hyperplasia with increased androgen receptors. J Am Acad Dermatol. Feb 1984;10(2 Pt 1):235-8. [Medline].
  23. Tate PR, Hodge SJ, Owen LG. A quantitative study of melanocytes in Becker's nevus. J Cutan Pathol. Dec 1980;7(6):404-9. [Medline].
  24. Tse Y, Levine VJ, McClain SA, Ashinoff R. The removal of cutaneous pigmented lesions with the Q-switched ruby laser and the Q-switched neodymium: yttrium-aluminum-garnet laser. A comparative study. J Dermatol Surg Oncol. Dec 1994;20(12):795-800. [Medline].
  25. Tymen R, Forestier JF, Boutet B, Colomb D. [Late Becker's nevus. One hundred cases (author's transl)]. Ann Dermatol Venereol. 1981;108(1):41-6. [Medline].
  26. Urbanek RW, Johnson WC. Smooth muscle hamartoma associated with Becker's nevus. Arch Dermatol. Jan 1978;114(1):104-6. [Medline].

Becker Melanosis excerpt

Article Last Updated: Oct 1, 2007