title: Two cases of dermatomyofibroma (plaque-like dermal fibromatosis).
abstract: BACKGROUND
  Dermatomyofibroma is a rare but distinct benign cutaneous mesenchymal neoplasm of fibroblastic/myofibroblastic differentiation. It is more common in adolescents and young adults, with a female preponderance. In most cases, the lesions are asymptomatic and small, measuring from 10 to 20 mm. Early and active lesions tend to be actin positive.
  
  
  METHODS
  We present a) a new case of dermatomyofibroma in an 11-month-old male infant, the youngest case reported to date, and b) the second reported case of a giant annular dermatomyofibroma, measuring 10 cm × 6 cm, in a 52-year-old woman. In both cases, histological examination showed a spindle-cell proliferation embedded among the collagen fibers of the dermis, arranged predominantly parallel to the skin surface. In both cases the spindle cells stained positive for smooth muscle actin and the elastic fibers were increased and fragmented.
  
  
  CONCLUSIONS
  Dermatologists and pediatricians should be aware of this benign entity in order to avoid unnecessary treatment.
authors.affiliation: Department of Dermatology, Carlos Haya Hospital, Malaga, Spain. eligm80@hotmail.com
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Gomez-Moyano
authors.forename: Angel
authors.initials: A
authors.lastname: Vera-Casaño
authors.forename: Silvestre
authors.initials: S
authors.lastname: Martinez-Garcia
authors.forename: Andrés
authors.initials: A
authors.lastname: Sanz-Trelles
authors.forename: Vicente
authors.initials: V
authors.lastname: Crespo-Erchiga
mesh_terms: D002455:Cell Division; D020405:Dermis / Q000473:pathology*; D005260:Female; D005347:Fibroblasts / Q000473:pathology*; D018219:Histiocytoma, Benign Fibrous / Q000175:diagnosis*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000473:pathology*; D012878:Skin Neoplasms / Q000175:diagnosis*