Giant adrenal myelolipoma: when trauma and oncology collide

Adrenal Myelolipoma Mimics Ectopic Adrenal or Renal Tissue: An Incidental Finding During Cadaveric Dissection

Context

On naked eye examination adrenal myelolipoma (AML) tissue appears to be an ectopic adrenal or renal tissue, based on the similarity to their external texture. This necessitates a histo-pathological study for confirming the origin of the tissue.

Objective

To establish the origin and histological features of the incidental AML tissue found during cadaveric dissection and review the literature for similar findings with clinical picture and treatment description.

Subjects and Methods

Unilateral adrenal gland obtained from cadaveric dissection was subjected to histological study by H & E staining of the slides prepared. The literature review was done from articles published in PubMed indexed journals.

Case report

A case of an incidental finding of AML during cadaveric dissection is presented which on naked eye examination was appearing to be an ectopic adrenal or renal tissue, based on the similarity to their external texture. On histological examination, a thin rim of adrenocortical tissue, surrounding the mature adipose tissue, and attenuated by islets of myeloid, erythroid and megakaryocytic cell lines in varying proportions, resembling the mature bone marrow morphology, was observed. The literature review on PubMed explains similar incidental post-mortem autopsy findings due to the asymptomatic nature of the tumor. The incidence of AML varied between 0.08% and 0.2% in the last decade of the 20^th century, which increased up to 10 - 15% of incidental adrenal masses due to the widespread use of non-invasive imaging modalities leading to an increase in the diagnosis of the pathology.

Conclusions

Before considering the ectopic incidence of tissue during cadaveric dissection, a histo-pathological examination is mandatory for confirmation. Adreno-myelolipoma is an asymptomatic post-mortem finding in 10-15% of cases of adrenal tissue which mimics ectopic adrenal gland or renal tissue due to its external texture.

Development of multiple adrenal myelolipomas after trauma-induced adrenal haemorrhage

Adrenal myelolipomas represent a benign neoplasm with known associations with many chronic diseases, 21-hydroxylase deficiency and cancer. However, the aetiology of adrenal myelolipomas remains unknown. Here, we present a case of a patient with image-proven bilateral adrenal haemorrhages caused by trauma with the subsequent development of bilateral adrenal myelolipomas several years later. Resection and pathological analysis of left adrenal gland confirmed the presence of multiple adrenal myelolipomas. Our case strongly suggests that trauma was the inciting event that led to the formation of these lesions.

Update on CT and MRI of Adrenal Nodules

OBJECTIVE

The objective of this article is to review the current role of CT and MRI for the characterization of adrenal nodules.

CONCLUSION

Unenhanced CT and chemical-shift MRI have high specificity for lipid-rich adenomas. Dual-energy CT provides comparable to slightly lower sensitivity for the diagnosis of lipid-rich adenomas but may improve characterization of lipid-poor adenomas. Nonadenomas containing intracellular lipid pose an imaging challenge; however, nonadenomas that contain lipid may be potentially diagnosed using other imaging features. Multiphase adrenal washout CT can be used to differentiate lipid-poor adenomas from metastases but is limited for the diagnosis of hypervascular malignancies and pheochromocytoma.