Adrenal myelolipomatous nodules mimicking adrenal neoplasms: report of three cases.

The authors describe three cases of adrenal myelolipoma. In the first two, unilateral adrenal masses, assumed to represent adrenal neoplasms, were found during urologic examination; the correct diagnosis was made by frozen-section examination during operation. The third case involved bilateral adrenal lesions diagnosed at autopsy in a patient suspected to have metastatic cancer. Histologic, immunohistochemical and electron microscopic studies revealed polyclonal lesions composed of hematopoietic cells and fat cells. Radiologic recognition and fine-needle biopsy of these lesions are important to avoid unnecessary surgery in asymptomatic cases. Since the lesions cannot be regarded as true neoplasms, the authors suggest that the name myelolipoma should be replaced by the term myelolipomatous nodule.