title: Pityriasis rubra pilaris with acantholysis and lichenoid histology.
abstract: Acantholytic foci have been reported several times in pityriasis rubra pilaris (PRP). Lichenoid tissue reactions were also mentioned in the literature regarding PRP. We report a 58-year-old patient who, after having colon cancer, had PRP with biopsies showing acantholytic lesions and a heavy lichenoid lymphocytic infiltration. Investigation by serial sectioning of the acantholytic lesion suggested an involvement of the intraepidermal eccrine duct and further investigation with carcinoembryonic antigen (CEA) staining demonstrated a CEA-positive eccrine duct in the acantholytic foci. We suggest that acantholysis in PRP is induced by proteolytic enzymes, urea, and other substances in eccrine sweat in keratin-plugged acrosyringia. This patient had a combination of three relatively rare features of PRP-acantholysis, lichenoid reaction, and a cancer background.
authors.affiliation: Department of Dermatology & Syphilology, Wayne State University School of Medicine, Detroit, Michigan, USA.
authors.forename: K
authors.initials: K
authors.lastname: Hashimoto
authors.forename: L
authors.initials: L
authors.lastname: Fedoronko
mesh_terms: D000051:Acantholysis / Q000378:metabolism / Q000473:pathology*; D002272:Carcinoembryonic Antigen / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017512:Lichenoid Eruptions / Q000378:metabolism / Q000473:pathology*; D008875:Middle Aged; D010916:Pityriasis Rubra Pilaris / Q000378:metabolism / Q000473:pathology*; D012867:Skin / Q000737:chemistry / Q000473:pathology
chemical_list: D002272:Carcinoembryonic Antigen