myofibromatosis, infantile, 1

Infantile myofibromatosis

Infantile myofibromatosis (IMF) is a rare tumor found in 1 in 150,000 to 1 in 400,000 live births. It is nonetheless the most common tumor derived from fibrous connective tissue that occurs primarily in infants and young children. IMF tumors are benign in the sense that they do not metastasize to distant tissues although when occurring in the viscera, i.e. internal organs, carry guarded to poor prognoses and can be life-threatening, particularly in newborns and young infants. The condition was first described by Arthur Purdy Stout as congenital generalized fibromatosis – in which he coined the word fibromatosis – in 1954. IMF tumors occur in three clinical patterns: 1) solitary IMF tumors (also called myofibromas) which often regress spontaneously and rarely cause serious issues; 2) multiple tumors (no viscera involvement) which consists of numerous (i.e. dozens to >100) IMF lesions most of which are located in the skin and subcutaneous tissues but not visceral organs, may regress spontaneously, and rarely cause serious issues; and 3) multiple tumors (with viscera involvement) (also called generalized myofibromatosis) which rarely regress spontaneously and consist of numerous IMF lesions in non-visceral tissues plus one or more visceral tumors that may be life-threatening. A minority of infantile myofibromatosis tumors present in individuals with a strong family history of the disease. These familial cases are associated with mutations in either the PDGFRB or NOTCH3 gene. However, most IMF cases have no family history of the disease but nonetheless have PDGFRB gene mutat...