Dermatology Online Journal

Epidermal nevus
Christopher T Cassetty MD, and Aimee L Leonard MD
Dermatology Online Journal 9(4): 43

From the Ronald O. Perelman Department of Dermatology, New York Univeristy

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Abstract

A 20-year-old woman presented with an asymptomatic, life-long, verrucous, hyperpigmented plaque on the face and neck that corresponded to the lines of Blaschko. Histopathologic examination shows an epidermal nevus. This nevus presents a challenge in management because of the location and extent of the lesion.

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Clinical summary

History.—A 20-year-old woman had a growth on the face and neck present since birth. The patient was evaluated at Bellevue Hospital Medical Center dermatology clinic in February 2003. She was referred for the evaluation of a growth on her face and neck of life-long duration. The lesion was asymptomatic and unchanged in color; however, it had increased in size as the patient grew. The patient never received treatment prior to this visit. Past medical history includes Type-I diabetes mellitus and hypertension.

Physical examination.—On the right side of the face and neck along the lines of Blaschko was a large, soft, hyperpigmented, cobblestone-like plaque with sharp but irregular borders. There was no lesional ulceration or regional lymphadenopathy. The ear was spared.

Figure 1	Figure 2

Laboratory data.—The laboratory findings are non-contributory.

Histopathology.—There is a reticulated and papillomatous epidermis with overlying orthohyperkeratosis. Some sebaceous glands connect with the epidermis. No apocrine or eccrine glands are noted.

Diagnosis.—Epidermal nevus.

Comment

There are two major classifications of epidermal nevi: non-organoid (keratinocytic) and organoid (sebaceous, follicular, and sweat gland). The type of epidermal nevus is determined by its predominant components. keratinocytes or epidermal appendages, both of which originate from embryonic ectoderm [1]. In this patient, the nevus is thought to be a keratinocytic type, with enlargement of sebaceous lobules secondary to the location of the lesion on the face.

Epidermal nevi are often present at birth but may develop as late as adolescence [1]. They are often asymptomatic; however, inflammatory linear verrucous epidermal nevi are pruritic. The characteristic epidermal nevus is a linear, hyperpigmented plaque, which can vary from pink to black, velvety to verrucous, subtle to thick, and limited to extensive. The lesion typically occurs on the trunk or extremities along the lines of Blaschko [2] but may occur on the face and neck. These lines are thought to represent examples of cutaneous mosaicism in embryologic development. Many syndromes with cutaneous manifestations have mosaic properties at the cellular level [2].

Well-defined epidermal nevus syndromes include congenital hemidysplasia with ichthyosiform erythroderma and limb defects (CHILD), Proteus syndrome, Schimmelpenning syndrome, nevus comedonicus syndrome, phacomatosis pigmentokeratotica, angora hair syndrome, and Becker nevus syndrome [1]. Rarely, squamous cell carcinoma, basal cell carcinoma, and keratoacanthoma have been associated with a keratinocytic epidermal nevus [1].

Management of epidermal nevi is challenging. Many therapies have been tried, including topical and intralesional glucocorticoids, topical and systemic retinoids, and topical 5-fluoruracil [4]. Destructive measures include dermabrasion, liquid nitrogen cryotherapy, laser therapy, and surgical excision [4, 5]. Surgical excision provides the best opportunity for complete remission but is complicated by the potential size of the scar in cosmetic areas.

References

1. Happle R, et al. Epidermal nevi. Adv Dermatol 18:175, 2002.

2. Bolognia JL, et al. Lines of Blaschko. J Am Acad Dermatol 31:157, 1994.

3. Happle R. New aspects of cutaneous mosaicism. J Dermatol 29:681, 2002.

4. Boyce S, et al. CO2 laser treatment of epidermal nevi: Long-term success. Derm Surg 28:611, 2002.

5. Lee BJ, et al. Full-thickness surgical excision for the treatment of inflammatory linear verrucous epidermal nevus. Ann Plast Surg 47:285, 2001.

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