Ultrastructural morphometry of different adrenal adenoma types

Twelve surgical specimens of adrenal tumors (3 mainly compact cell adenomas and 2 mainly spongiocytic adenomas of Cushing's syndrome, 4 adenomas of Conn's syndrome, 1 androgen-secreting adenoma, and 2 hormonally inactive tumors) were studied by ultrastructural morphometry, using the point-counting method. All groups were compared with regard to the statistical differences among the different cell organelles. Compact cell adenomas and spongiocytic adenomas in Cushing's syndrome revealed differences in the volume fraction of the following cell organefles: nuclei, smooth endoplasmic reticulum, mitochondria, Golgi zones, and unorganized cytoplasm, as well as in the fraction of lipid vacuoles. Compact cell adenomas in Cushing's syndrome were different from Conn's adenomas with respect to nuclei, smooth endoplasmic reticulum, rough endoplasmic reticulum, lysosomes, Golgi zones, and unorganized cytoplasm. Spongiocytic adenomas in Cushing's syndrome were different from adenomas in Conn's syndrome with respect to organized cytoplasm and lysosomes. Further data are given concerning the differences between Cushing's syndrome, adenomas in androgen-producing tumors, and inactive tumors. The statistically significant data were correlated with the functional expression of the different tumors. The morphometric studies confirmed the visually established ultrastructural features of adrenal tumors and provided further significant differences. Finally, these examinations obviously yielded specific patterns of the different adrenal adenoma types.