title: Fat-containing soft-tissue masses in children.
abstract: The diagnosis of soft-tissue masses in children can be difficult because of the frequently nonspecific clinical and imaging characteristics of these lesions. However key findings on imaging can aid in diagnosis. The identification of macroscopic fat within a soft-tissue mass narrows the differential diagnosis considerably and suggests a high likelihood of a benign etiology in children. Fat can be difficult to detect with sonography because of the variable appearance of fat using this modality. Fat is easier to recognize using MRI, particularly with the aid of fat-suppression techniques. Although a large portion of fat-containing masses in children are adipocytic tumors, a variety of other tumors and mass-like conditions that contain fat should be considered by the radiologist confronted with a fat-containing mass in a child. In this article we review the sonographic and MRI findings in the most relevant fat-containing soft-tissue masses in the pediatric age group, including adipocytic tumors (lipoma, angiolipoma, lipomatosis, lipoblastoma, lipomatosis of nerve, and liposarcoma); fibroblastic/myofibroblastic tumors (fibrous hamartoma of infancy and lipofibromatosis); vascular anomalies (involuting hemangioma, intramuscular capillary hemangioma, phosphate and tensin homologue (PTEN) hamartoma of soft tissue, fibro-adipose vascular anomaly), and other miscellaneous entities, such as fat necrosis and epigastric hernia.
authors.affiliation: Department of Medical Imaging, University of Toronto, Toronto, ON, Canada.|Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada.|Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Sheybani
authors.affiliation: Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Eric P
authors.initials: EP
authors.lastname: Eutsler
authors.affiliation: Department of Medical Imaging, University of Toronto, Toronto, ON, Canada. oscar.navarro@sickkids.ca.|Department of Diagnostic Imaging, The Hospital for Sick Children, 555 University Ave., Toronto, ON, M5G 1X8, Canada. oscar.navarro@sickkids.ca.
authors.forename: Oscar M
authors.initials: OM
authors.lastname: Navarro
mesh_terms: D002648:Child; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging; D006801:Humans; D018205:Neoplasms, Adipose Tissue / Q000000981:diagnostic imaging*; D012983:Soft Tissue Neoplasms / Q000000981:diagnostic imaging*
keywords: Adipocytic tumors; Children; Fat; Magnetic resonance imaging; Soft-tissue masses; Ultrasound