A 50-year-old woman presented with a 20-year history of slowly progressive red-to-brown pruritic hyperkeratotic papules and reticulated hyperpigmentation involving her face, neck, chest, back, and upper and lower extremities (Figure, A and B). She was previously diagnosed with Darier disease after biopsy revealed acantholytic dyskeratosis. She was treated with fluorouracil and tazarotene, 0.1%, cream with mild improvement, but she continued to develop new lesions. Social, family, and past medical history were noncontributory. Physical examination revealed reddish-brown hyperkeratotic papules on the neck, trunk, and extremities and diffuse brown macules, many in a reticulated pattern, on the face, neck, trunk, and extremities. There were no nail or mucosal changes. Laboratory data was noncontributory. A punch biopsy specimen was collected from both the arm and trunk and histologic examination was performed (Figure, C and D).