title: Onychomatricoma.
abstract: BACKGROUND
  Onychomatricoma is a rare benign tumor originating in the nail matrix. Only eight cases have been reported until now.
  
  
  OBJECTIVE
  The clinical and histopathological features of this recently reported tumor will be described and its differential diagnoses outlined. A typical case of onychomatricoma is described in a 62-year-old white man.
  
  
  RESULTS
  Clinically, onychomatricoma is characterized by: 1) a yellowish discoloration of a longitudinal segment of the nail plate with small splinter hemorrhages within the proximal portion of the nail; 2) a thickening with increased transversal curvature of the involved nail plate positively corresponding with the yellow discoloration; and 3) a matrix tumor consisting of multiple fine filiform projections that extend into the thickened nail plate. The treatment of onychomatricoma is complete excision of the tumor.
  
  
  CONCLUSIONS
  Onychomatricoma is a new entity with clinical and histopathological features that are characteristic enough to make the correct diagnosis.
authors.affiliation: Department of Dermatology, Hospitals of the City of Wuppertal, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Haneke
authors.forename: J
authors.initials: J
authors.lastname: Fränken
mesh_terms: D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008875:Middle Aged; D009260:Nail Diseases / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D009262:Nails / Q000473:pathology / Q000601:surgery; D009369:Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D013933:Thumb