IS Case 265: Adrenal myelolipoma

Scott Mooney, MD


Imaging Sciences URMC 2009
Publication Date: 2009-06-26

History

A 19-year-old male presented for a screening renal ultrasound for hydronephrosis. An MR was performed as follow up.

Findings

Echogenic mass superior to the kidney. Fatty mass originating from the right adrenal gland on MR.

Diagnosis

Adrenal myelolipoma

Discussion

A myelolipoma is most commonly a benign adrenal based neoplasm which is composed primarily of adipose tissue, but also contains hematopoietic elements. They are not common, with a reported incidence between 0.08-0.2%. Up to one-third may have calcification, which is best appreciated on CT. The risk of hemorrhage increases the larger the myelolipoma. They are rarely found extraadrenal, either in the retroperitoneum or presacral region. In the majority of cases they are considered non-surgical, unless there is compression of adjacent structures, pain, or hemorrhage. The diagnosis can be made on CT or MR with the demonstration of macroscopic fat, as fat-containing malignancies in the adrenal glands are extremely rare. On MR, this can be accomplished using fat-saturation.

References

  1. Cyran KM, Kenney PJ, Memel DS, Yacoub I. Adrenal myelolipoma. AJR Am J Roentgenol. 1996 Feb;166(2):395-400. PMID: 8553954 [PMID: 8553954]
  2. Pereira JM, Sirlin CB, Pinto PS, Casola G. CT and MR imaging of extrahepatic fatty masses of the abdomen and pelvis: techniques, diagnosis, differential diagnosis, and pitfalls. Radiographics. 2005 Jan-Feb;25(1):69-85. PMID: 15653588 [PMID: 15653588]

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