Pediatric Lipoma

  • Etiology: proliferation of mature fat tissue, subcutaneous in location
  • US: may have variable appearance (isocechoic, hyperechoic, hypoechoic to adjacent subcutaneous fat) and therefore not 100% diagnostic, minimal flow on Doppler
  • CT: negative Hounsfield unit is diagnostic
  • DDX: if patient is very young consider lipoblastoma, if lesion is painful or hyperechoic and or vascular consider angiolipoma
  • Clinical: most common fatty tumor in children, painless and slow growing but growth may accelerate with weight gain
  • Note: imaging cannot 100% reliably differentiate between lipoma, lipoblastoma, liposarcoma

Radiology Cases of Lipoma

CT of lipoma of the chest wall and thigh
Axial CT without contrast shows a symmetrical appearing chest wall (top), a fat density center-right sided chest wall mass (middle) and a fat density anterior left thigh mass (bottom).