Hematopoietic elements associated with adrenal glands. A study of the spectrum of change in nine cases.

We report nine cases of hematopoietic elements or myelolipomatous foci that were found in association with normal and neoplastic adrenal glands. A spectrum of change occurred that ranged from small clusters of purely erythroid or myeloid cells to microscopic myelolipomas that contained a mixture of hematopoietic elements. Recognition of the myeloid elements was facilitated with the use of the chloroacetate esterase (Leder) stain and a CD15 (myelomonocytic antigen) immunohistochemical stain. The majority (six of nine) of these cases were found in association with cortical adenomas in middle-aged women, but myelolipomatous foci were also found in association with an adrenocortical carcinoma, a pheochromocytoma, and a renal angiomyolipoma. The histogenesis of the foci remained speculative. However, the association with hormonally active neoplasms suggested that the hormonal microenvironment may have played a role in the development of the myelolipomatous foci.