Case Report: An incidentaloma that catches your eye - adrenal myelolipoma.

Background

Adrenal incidentaloma refers to the incidental finding of a tumor in the adrenal gland, where nonfunctional forms are the most common variant. Myelolipoma is a rare (0.08-0.4%) occurrence characterized by adipose and hematopoietic tissue. The aim of this case report is to describe the diagnosis and appropriate management of a myelolipoma in an asymptomatic patient, which was originally considered an incidental hepatic hemangioma prior to being identified as a giant adrenal adenoma. Case description: The patient was a 54 year old obese female with a recent diagnosis of diabetes type II and dyslipidemia with recent ultrasound imaging suggestive of a hepatic hemangioma. An MRI was performed revealing a 7x6cm lesion in the right adrenal area indicating a giant adrenal adenoma. An adrenalectomy was performed without complications. The pathology report identified a myelolipoma. Discussion: The incidence of myelolipoma has recently increased due to advances in radiological techniques. Its etiology is unclear and the most accepted theories support a myeloid cell metaplasia in the embryonic stage as a result of stress, infections, or adrenocorticotropic hormone or erythropoietin stimulus. Contributing components may include bone morphogenetic protein 2 and β-catenin, as well as the presence of the chromosomal translocation (3, 21) (q25; p11). Despite its benign nature, the association with other adrenal lipomas must be ruled out. A biochemical evaluation is essential for detecting subclinical states, such as Cushing syndrome and pheochromocytoma.

Conclusion

Adrenal myelolipomas are rare benign tumors that are generally asymptomatic. Uncertainty still exists surrounding their etiology. Surgical management depends on hormone production, tumor size, high risk features on imaging and patient consent.  Additional information is needed to better understand myelolipomas, their etiology, and clinical management.  Incidentalomas may confuse the physician and patient. Ensuring proper multidisciplinary management based on the clinical guidelines of endocrinology allowed a satisfactory resolution of this case.