Liu T H, Chen G S, Nan C, He Z G
Pathol Res Pract. 1984 Mar;178(4):355-62. doi: 10.1016/s0344-0338(84)80027-8.
58 tumors of pheochromocytoma from 55 cases were studied clinico-pathologically and electron-microscopically. In this series, males were predominant and the number of left adrenal pheochromocytomas was 1.6 times that of right ones. Extraadrenal pheochromocytomas amounted to 41.4%. All 5 malignant pheochromocytomas in this series arose from extraadrenal paraganglia. Two types of secretory granules corresponding to the epinephrine and norepinephrine granules in the normal adrenal medulla were discerned in all 13 tumors examined under electron microscope. The contents of different types of granules were compared with urinary catecholamine excretion, and no apparent correlation was disclosed. Large amount of "E" granules in tumor cells of some cases might be associated with very low level of urinary epinephrine, while in the other cases, the reverse was true. The amount of catecholamine excreted in urine also bore no relation to the size of the tumor.
