This is a type of fibromatosis that typically affects children less than five years of age. Patients are usually brought to a physician's attention because of the discovery of a large mass. The most common sites of involvement are the shoulder irdle and muscles and fascia of the head and neck and thigh. Involvement of the long bones may be associated with tumors of the leg. Infantile fibromatosis does not metastasize but can recur locally following surgical excision. The treatment philosophy is to perform as complete a surgical excision as possible without interfering with function or causing disfigurement.