Linear, pruritic red to brown papules on the left chest.

A 28-year-old woman presented with a 12-year history of red to brown papules in a linear distribution on the left lateral chest associated with recent flares of pruritus. She had previously been clinically diagnosed with lichen planus. A punch biopsy was performed, and histopathologic exam revealed Darier-like acantholysis. The patient was diagnosed with type 1 segmental Darier disease and her symptoms improved with topical tretinoin.