title: Plexiform and other unusual variants of palisaded encapsulated neuroma.
abstract: Palisaded, encapsulated neuroma (PEN) has been described as a predominantly solitary, nodular tumor; plexiform or multinodular growth patterns have not been reported in detail. We reviewed 55 PEN in order to evaluate: 1) the predominant growth patterns; 2) features that may indicate previous trauma; and 3) association with acne-like changes. Sixteen cases (29%) had growth patterns other than the solitary, nodular type. These patterns were: a) plexiform (7/16), b) multinodular (5/16), and c) fungating (4/16). Other unusual features included evidence of trauma, i.e., fibrosis, myxoid change, chronic inflammation (5/16), partially incomplete capsule (6/16), and association with acne-like features (13/16). These results suggest that: 1) plexiform or multinodular growth patterns occur relatively often in PEN; 2) some changes indicate a possible histogenetic relation to traumatic neuroma, probably via secondary traumatization; 3) a high frequency of association with acne-like changes which could imply, but does not prove, an acne-induced histogenesis; and 4) the differential diagnosis of cutaneous plexiform lesions should include PEN.
authors: Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City 52242-1009.
authors: Z B
authors: ZB
authors: Argenyi
authors: P H
authors: PH
authors: Cooper
authors: D
authors: D
authors: Santa Cruz
mesh_terms: D000152:Acne Vulgaris / Q000150:complications; D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000032:analysis; D003094:Collagen / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D008875:Middle Aged; D018396:Mucin-1; D009455:Neurofibroma / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D009463:Neuroma / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D014947:Wounds and Injuries / Q000150:complications
chemical_list: D000951:Antigens, Neoplasm; D008562:Membrane Glycoproteins; D018396:Mucin-1; D003094:Collagen