Adrenal gland and paraganglia
Other benign cortical lesions

Author: Nat Pernick, M.D. (see Authors page)

Revised: 1 March 2016, last major update February 2005

Copyright: (c) 2002-2016,, Inc.

Cite this page: Myelolipoma. website. Accessed January 22nd, 2017.
Definition / General
  • Rare, benign and usually solitary tumor composed of hematopoietic precursor cells and mature fat
  • Usually an incidental autopsy finding (0.1 to 0.2% of cases) or incidental CT / MRI finding
  • Not associated with hematologic disorders; non-functioning
  • Most patients are obese adults (mean age 50 years)
  • May have areas of fibromyxoid degeneration resembling low-grade fibromyxoid sarcoma
  • Focal myelolipomatous change also in adrenocortical hyperplasia and tumors; usually incidental (Arch Pathol Lab Med 1994;118:895)
  • May be metaplastic change in reticuloendothelial cells of blood capillaries in response to necrosis, infection or stress
Case Reports
  • Follow up or excision if symptomatic
Gross Description
  • Non-encapsulated, bright yellow adipose-like tissue with hemorrhagic foci (contains marrow tissue)
  • May be up to 5 kg
Gross Images

24 cm tumor
    Micro Description
    • Mature islands of hematopoietic cells and mature fat
    • Larger tumors may have hemorrhage, necrosis, calcification and cyst formation
    Micro Images

    Images hosted on other servers:

    With ganglioneuroma

    Various images - mature adipose and hematopoietic cells

    Classic Tumor

    Differential Diagnosis