Adrenal cysts: pathogenesis and histological identification with a report of 6 cases.

Because of their rarity cysts of the adrenal gland are often misinterpreted and misdiagnosed. Six cases of surgically removed adrenal cysts are presented, including 3 endothelial cysts, 2 epithelial retention cysts and 1 pseudocyst. Evidence is presented that epithelial retention cysts could and do develop in the human adrenal cortex and are not theoretically impossible as propagated in the literature. We also emphasize the importance of evaluating the surrounding fibrous and adrenal tissue in the proper identification of these cysts, a point not sufficiently stressed previously.