Melanoma arising in segmental nevus spilus: detection by sequential digital dermatoscopy.

Abstract

Nevus spilus (NS) defines a café-au-lait macule with superimposed maculopapular speckles. Although the café-au-lait macule often presents at birth, the darker pigmented speckles increase in number and size during a period of several years. The need for close follow-up of patients with NS is underlined by reports of several cases of cutaneous melanoma developing within such lesions. We followed up 4 adult patients (3 male, one female; mean age 38 years) with unilateral segmental NS of the thoracic or abdominal region. The NS was present at birth in all 4 patients. Follow-up by sequential digital dermatoscopy and digital overview images was scheduled every 6 to 12 months. During surveillance (mean follow-up time, 8.15 years), 3 melanocytic lesions were excised. In one patient focal enlargement prompted excision of two dysplastic compound nevi. In another patient new black dots and focal peripheral hyperpigmentation were detected by comparison with previous images. Histologic analysis confirmed the diagnosis of invasive melanoma (Breslow thickness, 0.6 mm). This observational clinical study included a small number of patients. Sequential digital dermatoscopy of large NS in children may lead to unnecessary excisions because of physiologic changes. We suggest close follow-up of patients with segmental NS whenever complete excision is not possible. In adults, follow-up by digital dermatoscopy and excision of lesions with dynamic changes may assist in the early detection of melanoma.