An 18-year-old Caucasian male presents for evaluation of a growth on his leg that he first noted in early childhood. During the past several years, the lesion has increased in size and has darkened in color. He denies both personal and family history of skin cancer. Examination of his abdomen reveals a hyperpigmented, irregularly shaped verrucoid plaque. Full body examination is otherwise unremarkable.
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Epidermal nevi are present at birth or arise in early childhood and often follow lines of Blaschko.1 They are usually flesh colored at onset but may darken over time, and some develop a verrucoid appearance with hyperkeratosis, aptly termed verrucous epidermal nevi (VEN). VEN involve keratinocytes as opposed to other epidermal nevi that are composed of hair follicles or sebaceous glands.2 About 40% are associated with mutations in the FGFR3 and PIK3CA genes that provide instructions for making proteins involved in cellular signaling.3 Rarely, VEN may be associated with internal abnormalities as part of the epidermal nevus syndrome.4
Surgical excision is curative. Malignant transformation is extraordinarily uncommon but has been reported, and biopsy is prudent should a lesion develop atypical features.5
Rebecca Geiger, PA-C, is a physician assistant on staff at the DermDox Dermatology Center in Hazleton, Pennsylvania. Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia.
- 1. Rogers M, McCrossin I, Commens C. Epidermal nevi and the epidermal nevus syndrome. A review of 131 cases. J Am Acad Dermatol. 1989;20:476-488.
- 2. Brandling-Bennett HA, Morel KD. Epidermal nevi. Pediatr Clin North Am. 2010;57:1177-1198.
- 3. Miranda LQ, Fracaroli TS, Fonseca JC, et al. Analysis of mutations in the PIK3CA and FGFR3 genes in verrucous epidermal nevus. An Bras Dermatol. 2013;88(6 Suppl 1):36-38.
- 4. Kumar CA, Yeluri G, Raghav N. Inflammatory linear verrucous epidermal nevus syndrome with its polymorphic presentation – a rare case report. Contemp Clin Dent. 2012;3:119-122.
- 5. Yarak S, Machado TY, Ogawa MM, Almeida ML, Enokihara MM, Porro AM. Squamous cell carcinoma arising in a multiple verrucous epidermal nevus. An Bras Dermatol. 2016;91(5 Suppl 1):166-168.