Histochemical Nature of Eosinophilic Globules in Pheochromocytoma of Adrenal Medulla

Eosinophilic globules were observed in 7 out of 11 cases of pheochromocytoma of the adrenal medulla. All of these globules were present in the cytoplasm, and were round and eosinophilic, measuring 3 μm to 30 μm in diameter. These globules were periodic acid Schiff (PAS) -positive with and without diastase predigestion, phosphotungstic acid hematoxylin (PTAH) positive, acid fuchsin positive, and autofluorescent under ultraviolet illumination. These findings were very similar to the eosinophilic globules of yolk sac tumor, hepatocellular carcinoma, Kaposi\u27s sarcoma, and alpha-l-antitrypsin deficiency in light microscopy and histochemistry. They were not stained with Grimelius\u27s method for argyrophil reaction, and Fontana-Masson\u27s method for argentaffin reaction. It might be suggested that eosinophilic globules in pheochromocytoma of the adrenal medulla were not related to the chromaffin secretory granules and these globules were glycoprotein