[Ultrastructure of a steroid-producing adrenal cortex tumor and another one without endocrine activity]

Electron-microscopic investigations on two human adrenal gland tumors have been carried out. The glucocorticoid and androgen producing tumor predominantly showed mitochondria similar to those of normal human zona fasciculata and zona reticularis. On the other hand, the non hormone producing tumor failed to imitate typical adrenal gland mitochondria. "Light" and "dark" cells were seen like in the normal adrenal cortex. Although a few liposomes were found in nearly all cells only 6 to 8% of the cells contained liposome numbers comparable to normal adrenal gland. A possible explanation is discussed.