A cystic lesion should be distinguished from focal cystic degeneration in an adrenal tumor.
Cystic lesions of the adrenal include:
(1) pseudocyst (without a cell lining, usually secondary to hemorrhagic or ischemic degeneration within an adrenal tumor)
(2) endothelial (angiomatous or lymphangiomatous with endothelial cell lining)
(3) epithelial
(3a) embryonal rest
(3b) true glandular cysts (with a epithelial cell lining)
(3c) cystic adrenal neoplasm (see below)
(4) parasitic
Adrenal tumors which may present as a cystic neoplasm include:
(1) adrenocortical carcinoma
(2) adrenocortical adenoma
(3) pheochromocytoma
(4) metastatic carcinoma
Foci of tumor in a cystic adrenal neoplasm may be small so extensive sampling of the cyst wall must be performed before a neoplasm is excluded.
An adrenal cyst may be:
(1) asymptomatic
(2) symptomatic due to compression of adjacent structures
(3) symptomatic from hormone production
(4) associated with abdominal pain