title: Dermal spindle cell lipoma: plexiform and nodular variants.
abstract: We report on eleven cases of a distinctive dermal spindle cell lipoma characterized by a mixture of mature adipocytes and spindle-shaped cells in a fibromucinous background. Six lesions showed a moderately well circumscribed plexiform pattern, five a well demarcated nodular pattern with compression of surrounding connective tissue and prominent stromal fibrosis. Clinically, the plexiform type mostly occurred in the thigh-groin-buttock area and the nodular type in the head-neck or acral location. While plexiform lesions were predominantly seen in middle-aged females, nodular types occurred in young adults of either sex. No recurrence was seen in five patients with follow-up. The tumour cells were vimentin positive and a thin cytomplasmic rim of S-100 protein positivity was seen in mature adipocytes. Ultrastructural studies revealed lipoblastic differentiation of spindle-shaped cells with lipid droplets and basal lamina formation. Dermal spindle cell lipomas seem to be the dermal counterpart of the most subcutaneously located spindle cell lipoma.
authors.affiliation: Department of Dermatology, University of Innsbruck, Austria.
authors.forename: B W
authors.initials: BW
authors.lastname: Zelger
authors.forename: B G
authors.initials: BG
authors.lastname: Zelger
authors.forename: A
authors.initials: A
authors.lastname: Plörer
authors.forename: H
authors.initials: H
authors.lastname: Steiner
authors.forename: P O
authors.initials: PO
authors.lastname: Fritsch
mesh_terms: D017667:Adipocytes / Q000648:ultrastructure; D000293:Adolescent; D000328:Adult; D000906:Antibodies; D002648:Child; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008055:Lipids / Q000737:chemistry; D008067:Lipoma / Q000737:chemistry / Q000473:pathology*; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D012189:Retrospective Studies; D012983:Soft Tissue Neoplasms / Q000737:chemistry / Q000473:pathology*
chemical_list: D000906:Antibodies; D008055:Lipids