title: Cutaneous pseudosarcomatous polyp: a histological and immunohistochemical study.
abstract: Two unusual acquired polypoid skin lesions exhibited prominent histological atypia, but were biologically benign. Both patients were elderly females. The lesions clinically mimicked fibroepithelial polyp or nevus lipomatosus. Both had been present for about 20 years. One lesion was located on the back, the other on the posterior thigh. Each lesion exhibited dilated, hyalinized vessels in the dermis with focal fibrin deposits, myxoid stroma, and a population of bizarre, pleomorphic spindle to stellate cells, some of which were multinucleated. Occasional atypical mitoses were present. One lesion had abundant admixed fat. Immunohistochemical staining was strongly positive only for vimentin. The lesions share features with degenerating angiofibroma and vaginal pseudosarcomatous polyp. As in these lesions, the atypia is most probably reactive and degenerative.
authors.affiliation: Department of Dermatology and Pathology, University of California, Irvine, USA.
authors.forename: B T
authors.initials: BT
authors.lastname: Williams
authors.forename: R J
authors.initials: RJ
authors.lastname: Barr
authors.forename: T L
authors.initials: TL
authors.lastname: Barrett
authors.forename: M A
authors.initials: MA
authors.lastname: Everett
authors.forename: F
authors.initials: F
authors.lastname: Lin
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008875:Middle Aged; D011127:Polyps / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology*; D013848:Thigh