The patient is a 47-year-old female requesting full body examination, as she has multiple moles and a family history of skin cancer. She has also experienced ample lifetime sun exposure. Numerous nevi are noted, none clinically or dermatoscopically suspicious. She states that a mole on her shoulder was removed twice during the past 15 years, but each time coloration returned. Examination reveals a hyperpigmented, irregularly shaped macule. Under the dermatoscope, a homogeneous pattern of pigmentation was observed with dots and globules.
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Incomplete excision of pigmented nevi may result in recurrence of coloration within the site. An extensive review of 175 cases of recurrent nevi found a striking female predominance (85%) with the majority of lesions located on the trunk.1 All patients were Caucasian, and the predominant age range was between 20 and 30 years. The interval between recurrence and primary removal was approximately 5 years. The lesions were smaller than 1.5 cm in diameter and were characterized by irregular hyperpigmentation.
Recurrent nevi may pose a diagnostic challenge under the microscope, and the histopathologic appearance has been referred to as “pseudomelanoma.”2 This nomenclature has been challenged by other analyses that highlight the benign characteristics of these lesions.1 Dermatoscopic examination is highly recommended, and classic features include streaks, pigmented network, dots and globules, and background homogeneous pigmentation.3 Rather than reexcision, periodic dermatoscopic monitoring is a reasonable course of action.4
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.
- Park HK, Leonard DD, Arrington JH 3rd, Lund HZ. Recurrent melanocytic nevi: clinical and histologic review of 175 cases. J Am Acad Dermatol. 1987;17(2 Pt 1):285-292.
- Kornberg R, Ackerman AB. Pseudomelanoma: recurrent melanocytic nevus following partial surgical removal. Arch Dermatol. 1975;111:1588-1590.
- Botella-Estrada R, Nagore E, Sopena J, et al. Clinical, dermoscopy and histological correlation study of melanotic pigmentations in excision scars of melanocytic tumours. Br J Dermatol. 2006;154:478-484.
- Salerni G, Terán T, Puig S, et al. Meta-analysis of digital dermoscopy follow-up of melanocytic skin lesions: a study on behalf of the International Dermoscopy Society. J Eur Acad Dermatol Venereol. 2013;27:805-814. doi: 10.1111/jdv.12032.