title: Superimposed segmental hemangioma of infancy.
abstract: BACKGROUND
  Segmental hemangioma of infancy is sometimes associated with the development of multiple nonsegmental hemangiomas. Such co-occurrences have so far remained unexplained.
  
  
  RESULTS
  Pertinent reports were collected from the literature. To explicate such cases, the following concept is proposed. Hemangiomas of infancy reflect a polygenic predisposition. Nonsegmental lesions result from a mutational event occurring at a late stage of intrauterine life or after birth, whereas segmental hemangioma originates from loss of heterozygosity or some other mutational event arising at an early developmental stage.
  
  
  CONCLUSIONS
  In this way, segmental hemangioma of infancy could be taken as a further example of the superimposed segmental manifestation of a polygenic skin disorder. Future molecular research may show whether this assumption holds true.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Happle
mesh_terms: D005260:Female; D006391:Hemangioma / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007223:Infant; D019656:Loss of Heterozygosity; D020412:Multifactorial Inheritance; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology