[A clinicopathological and ultrastructural study on 147 cases of primary aldosteronism].

147 cases of primary aldosteronism was analysed, including 133 cases of adenoma (90%), 13 cases of cortical hyperplasia, and 1 case of carcinoma. The size of aldosteronoma was usually 1-2 cm in diameter. All the adenomas were well capsulated and the cut surface showed a homogeneous yellow color. The largest one in this group was 6 cm in diameter. The diameter of aldosteronoma was over 10 cm and the cut surface showed a brownish yellow color. Microscopically, the aldosteronoma was composed principally of clear cells arranged in a glomerular pattern, while the malignant one consisted of more granular cells with nuclear atypia and mitoses. Ultrastructure of the majority of tumor cells showed presence of numerous lipid vacuoles representing content of the steroid hormones. In those patients who had received spironolactone before operation, some eosinophilic concentric laminated spironolactone bodies could be obtained in the lipid vacuoles, which indicated that the steroid hormone had been blocked or destroyed. Additionally, the laminated cristae within the mitochondria in aldosteronoma looked closely similar to those of the normal cells in the zona glomerulosa, suggesting that these tumors are mainly derived from zona glomerulosa of the adrenals.