title: A leiomyoma of the iris documented by immunohistochemistry and electron microscopy.
abstract: OBJECTIVE
  To report an iris leiomyoma documented in accordance with today's stricter diagnostic criteria.
  
  
  METHODS
  Light microscopy, immunohistochemistry and electron microscopy were performed on the 3 mm ball-like, greyish-white vascularized tumour of the iris, close to the sphincter pupillae.
  
  
  RESULTS
  Light microscopy of the extirpated neoplasm showed the characteristic appearance of a leiomyoma with densely packed spindle-shaped cells, with oval nuclei and granular cytoplasm. On electron microscopic examination the tumour exhibited the characteristic features of a smooth muscle neoplasm. The immunohistochemistry was consistent with a myogenic tumour because the tumour cells were positive for smooth muscle actin and desmin, but negative for S-100 and melanin.
  
  
  CONCLUSIONS
  The case illustrated the necessity of performing ancillary procedures such as electron microscopy and immunohistochemistry to substantiate a correct, although rare diagnosis.
authors.affiliation: University Eye Department, The National Hospital, Rikshospitalet, University of Oslo, Norway.
authors.forename: N
authors.initials: N
authors.lastname: Eide
authors.forename: I N
authors.initials: IN
authors.lastname: Farstad
authors.forename: M
authors.initials: M
authors.lastname: Røger
mesh_terms: D000199:Actins / Q000378:metabolism; D000328:Adult; D003893:Desmin / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D015811:Iris Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure*; D007889:Leiomyoma / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure*; D008297:Male; D008543:Melanins / Q000378:metabolism; D008854:Microscopy, Electron; D009418:S100 Proteins / Q000378:metabolism
chemical_list: D000199:Actins; D003893:Desmin; D008543:Melanins; D009418:S100 Proteins