Adrenal myelolipoma

  • Rare
  • Benign, non-functioning
  • Adrenocortical dysfunction in 10%
  • <5 cm, solitary
  • Hematopoietic precursor cells and mature adipose tissue 
  • May have fibromyxoid degeneration, hemorrhage, necrosis, calcification
  • Asymptomatic 
  • Large lesions sometimes cause abdominal pain or retroperitoneal bleeding
Imaging 
  • Recognizable capsule
  • May have calcification
  • Varying amounts of fat
  • Myeloid soft tissue component enhances with contrast
  • Fat attenuation < -30 HU is typical. Adenomas HU mostly never falls below -20