A red nodule of the scalp

A 49-year-old Caucasian man was referred to our Unit for the recent occurrence of a nodular lesion on a long-standing nevus. A smooth, dome-shaped, reddish lesion, 1 cm in diameter, on a flesh-colored plaque with a velvety and verrucous surface was observed (Figure 1). Dermoscopy of the nodule showed yellow to pink-colored lobules of different sizes, interposed by whitish pale septae. Glomerular and hairpin vessels were detected (Figure. 2). The underlying plaque revealed yellowish/orange structures sometimes gathered in clusters. The entire lesion was excised. Microscopic examination revealed cystic invaginations: the upper parts were lined by epithelial cells that resembled those present on the surface epidermis, and the lower parts were characterized by irregular papillary projections of various size and aspect. The epithelium was made up of two layers of cells that were cylindrical at the luminal side and cuboidal at the base. Dilated capillaries, decapitation secretion, and plasmocyte-rich inflammatory infiltrate within papillary projections were observed (Figure 3). A red nodule of the scalp