title: Mast cell numbers in multiple dermatofibromas.
abstract: BACKGROUND
  Multiple dermatofibromas (DFs) have been reported to develop in various disorders, especially in systemic lupus erythematosus (SLE).
  
  
  OBJECTIVE
  To investigate the role of mast cells in the formation of multiple DFs in association with autoimmune disorders, we quantified the number of mast cells.
  
  
  METHODS
  Three cases who developed multiple DFs with positive antinuclear antibodies are described; a 54-year-old woman with a 10-year history of SLE with 13 lesions, a 33-year-old woman with 11 lesions and a 46-year-old woman with SLE and Sjögren syndrome with 10 nodules. Distribution and number of mast cells were examined in the removed lesions of DFs.
  
  
  RESULTS
  In 2 cases, mast cells in the upper portion of the lesions were increased in number in comparison with the solitary DF, nevocellular nevus and normal skin. These 2 cases had early DFs from the onset; in the remaining case in which mast cell number was not increased, they were old or fading lesions.
  
  
  CONCLUSIONS
  It is suggested that mast cells may play a role in induction and exacerbation of the fibrotic process of multiple DFs, and they are supposed to be a reactive hyperplasia in association with systemic autoimmune disorders.
authors.affiliation: Department of Dermatology, School of Medicine, Tokyo Medical and Dental University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: I
authors.initials: I
authors.lastname: Katayama
authors.forename: K
authors.initials: K
authors.lastname: Nishioka
mesh_terms: D000328:Adult; D000974:Antibodies, Antinuclear / Q000096:biosynthesis; D001706:Biopsy; D002452:Cell Count; D005260:Female; D018219:Histiocytoma, Benign Fibrous / Q000209:etiology / Q000276:immunology* / Q000473:pathology*; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000150:complications; D008407:Mast Cells; D008875:Middle Aged; D012878:Skin Neoplasms / Q000209:etiology / Q000276:immunology* / Q000473:pathology*; D013997:Time Factors
chemical_list: D000974:Antibodies, Antinuclear