Sipple's syndrome with peculiar changes in pancreatic islets--an autopsy case.

A diagnosis of the heritable disorder Sipple's syndrome was made in a Japanese male aged 28 years. The coexistence of bilateral phenochromocytomas, bilateral medullary thyroid carcinomas and secondary hyperplasia of parathyroid was confirmed at the time of autopsy. Pancreatic islets were hyperplastic with marked proliferation of A and D cells. Transition of the ductal cell to the islet, i.e. "nesidioblatosis" was observed. There was no proliferation of B cells, but a retention of B cell granules, a manifestation of suppressed secretion of insulin attributed to the overproduction of catecholamines was evident. In the stomach, numerous petechial hemorrhages and proliferation of gastrin cells were found. The pathogenesis of changes in the pancreatic islets and stomach is discussed from the viewpoint of hormonal disorders induced by pheochromocytoma and medullary thyroid carcinoma such as are found in Sipple's syndrome.