title: [Solitary cutaneous infantile myofibromatosis].
abstract: Infantile myofibromatosis is the most frequent fibromatosis in childhood. It is a benign proliferation of fibroblasts and myofibroblasts. This case report concerns a newborn who presented at birth with a purple cutaneous nodule on the scalp. Surgical excision was performed at the age of 16 months. Infantile myofibromatosis was diagnosed on histology. Infantile Myofibromatosis (IMF) was first described by Enzinger in 1981. Three types can exist. Solitary MFI, the most frequent, is a solitary lesion, cutaneous/subcutaneous, osseous or involving soft tissues. Multicentric disease is characterized by multiple locations and generalized form by visceral involvement. Morphological features are identical in all types. The histological diagnosis relies on the identification of two separate components, a fascicular myofibroblastic pattern at the periphery with a hemangiopericytoma like pattern in the centre. Both components are positive for alpha-smooth muscle actin. Atypia, or mitotic activity, are not observed usually but features of intravascular growth can be seen in the centre of the lesion. Infantile MF carries a good prognosis when solitary but death frequently occurs in generalized MF with visceral involvement.
authors.affiliation: Service d'anatomie et de cytologie pathologiques, Hôpital Bichat - Claude Bernard, 46 rue Henri Huchard, 75018 Paris. tom.petit@online.fr
authors.forename: Thomas
authors.initials: T
authors.lastname: Petit
authors.forename: Maggy
authors.initials: M
authors.lastname: Grossin
authors.forename: Sylvie
authors.initials: S
authors.lastname: Fraitag
authors.forename: Dominique
authors.initials: D
authors.lastname: Hénin
mesh_terms: D006801:Humans; D007150:Immunohistochemistry; D007231:Infant, Newborn; D008297:Male; D018224:Myofibromatosis / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D011379:Prognosis; D012535:Scalp; D012878:Skin Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery