Congenital lipoblastomatosis of the lower extremity in a neonate

Lipoblastomatosis is a benign tumor of embryonic fat that is more common in male infants. It occurs more frequently in the soft tissues of the extremities. The diagnosis is made by biopsy, which shows globules of lipocytes and lipoblasts mixed with spindled and myxoid cells. MRI demonstrates fat infiltrating fascia and muscle. The infant described had clinical, histologic, and radiologic findings consistent with this diagnosis. Because of concern that total excision would compromise function, a debulking procedure is planned.