Bilateral adrenal myelolipoma

Myelolipomas are rare benign tumors often found incidentally due, in the ma jority of cases, to the fact that they are asymptomatic. The incidence of a drenal myelolipomas at autopsy is low (0.2%). These tumors are made up of f at and hematopoietic cells. Their origin is unclear and different theories have been put forward, including development from rests of mesenchymal stem cells, embolism of bone marrow, extramedullary hematopoiesis and, accordin g to the most widely accepted theory, metaplasia of the reticuloendothelial cells of blood capillaries. Due to their uncertain etiology and low freque ncy, management of adrenal myelolipomas is usually individualized and carri ed out depending on the protocols of each center. The development of improv ed imaging techniques has increased their diagnosis in routine clinical pra ctice. Thus, they have been included in the heterogenous group of 'incident alomas' of the adrenal gland. Copyright (C) 1999 S. Karger AG, Basel.