An initial biopsy specimen from the right areola showed spongiotic psoriasiform dermatitis with a superficial infiltrate of eosinophils and lymphocytes. Eosinophils were noted at the dermoepidermal junction. A second biopsy specimen from the edge of a plaque on the right breast was similar. Direct immunofluorescence showed linear deposition of C3 and IgG at the dermoepidermal junction. Indirect immunofluorescence on salt-split skin showed immunoreactants on the roof of the salt-induced blister.
Urticarialike Plaques on the Breasts of a 72-Year-Old Woman—Diagnosis. Arch Dermatol. 2005;141(9):1161-1166. doi:10.1001/archderm.141.9.1161-f