A review of clinicopathologic features of pheochromocytomas in Hong Kong Chinese.

Twenty-two Chinese patients with pheochromocytomas including 18 surgical and four autopsy cases were reported. The incidence at autopsy was 0.048%. The tumours were most common in the sixth and the fourth decades in males and females, respectively. There was no sex predilection. The incidence of bilaterality was 4.5% and the tumours were more common on the right side. 9.1% of the tumours were malignant and they were larger than their benign counterparts. Solid and diffuse pattern and mixed pattern were the most common histologic patterns. Minor histological features included hyaline globules (64%), nuclear pseudo-inclusions (55%), lipid degeneration (4.5%) and peri-adrenal brown fat (18%). All of them were strongly positive for the three pan-neuroendocrine markers (neuron-specific enolase, synaptophysin and chromogranin) confirming the usefulness of these markers in diagnosing pheochromocytoma.