Myelolipoma in a heterotopic adrenal gland: light and electron microscopic findings.

A symptomatic myelolipoma of the heterotopic adrenal gland was diagnosed as the cause of nephrotic syndrome and was surgically removed. Remission of the nephrotic syndrome promptly ensued. Ultrastructurally, the tumor consisted of well-differentiated cells resembling adrenal cortical cells, bone marrow cells in various stages of differentiation, and lipid cells. Some cells that contained fat were of adrenal cortical origin, but the derivation of most lipid cells and of bone marrow elements could not be deduced from the present ultrastructural findings.