hamartoma of the skin Q85,91

Hamartoma of the skin (synonymous with "nevus") is a visible, sharply circumscribed, often congenital, but also postnatally manifesting, long-term malformation of the skin or mucosa, which is characterized by excess, more rarely also by underdevelopment or malformation, of one or more components of skin or mucosa, and which etiopathogenetically reflects a cutaneous mosaic (see also under malformation).

Hamartomas are named after the predominant structure, e.g., sebaceous gland s. Nevus sebaceus, sweat glands s. Hamartoma ekkrines, melanocytes s. Nevus melanocytärer, connective tissue s. Connective tissue naevus, hamartoma fibrinous, blood vessels s. Hamangioma, nevus flammeus ,s.a. malformation vascular, u.s.w. compare also malformation. Combined malformations are possible, whereby the predominant tissue type gives the name. Systematized hamartomas are those which are distributed over a body region. They follow in their arrangement either a dermatome, but more frequently the Blaschko lines (classification see under nevus).

Hamartoma of the skin is caused, for example, by abnormal development of individual components of the skin, epidermis or skin appendages, vessels or nerves or skin connective tissue, according to a genetic mosaic.

1st Grundmann (2018) Dignity of tumors. Kurzlehrbuch Pathologie p. 205 Elsevier Munich.

2 Zelger B (2003) Nerve-muscle-cartilage-bone and adipose tissue tumors of the skin. In: Kerl H et al. (eds) Histopathology of the skin, p. 816 Springer Verlag, Berlin Heidelberg New York.

3 Happle R (2004) Cutaneous mosaics: patterns and molecular mechanisms. Dt Ärzteblatt 101: 1575-1580