Lipomatous Changes in Adrenocortical Adenomas: Report of Two Cases.

Rare cases of myelolipomas associated with adrenocortical lesions responsible for Cushing or Conn syndromes have been described. We report two additional cases of extensive lipomatous changes in incidentally discovered adrenocortical adenomas, which were preoperatively interpreted as myelolipomas on the basis of radiologic findings. Microscopically, the adenomas were composed of sheets and nests of adrenocortical cells, and extensive areas of mature adipose tissue admixed with a bland stromal infiltration of small cells. The impression was that myeloid cells were present, featuring a myelolipoma associated with a clear cell adenoma of the adrenal cortex, but specific immunocytochemical markers of myeloid lineage were not reactive in the small cell component, and these cells consisted of small lymphocytes. The lipomatous tissue may represent a degenerative phenomena within an adrenocortical adenoma or may be an additional neoplastic component of the tumor. Irrespective of their origin, extensive (myelo)lipomatous changes in adrenocortical tumors can lead to misinterpretations in the preoperative work-up of patients with adrenal masses.