Lentiginous naevi in the elderly may have atypical dermoscopic features and may require biopsy to exclude transition to melanoma.
Over a 12-month period, a 75-year-old man developed an irregular pigmented lesion, measuring 4 mm in diameter, on his anterior chest. Dermoscopy revealed an asymmetrical lesion with an irregular light brown to dark brown network and a black homogeneous area with dark globules. Excision biopsy showed an epidermis with a well formed pigmented rete ridge system containing increased melanocytes and isolated nests. The upper dermis showed focal lymphocytic inflammation and pigment deposits.