Superimposed segmental hemangioma of infancy

Segmental hemangioma of infancy is sometimes associated with the development of multiple nonsegmental hemangiomas. Such co-occurrences have so far remained unexplained.

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.

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.