Cystic adrenal neoplasms

BACKGROUND. Cystic lesions of the adrenal gland are uncommon and demonstrate a spectrum of histologic changes and may vary from pseudocysts to malignant cystic neoplasms. METHODS. The authors analyzed a series of primary cystic lesions of the adrenal gland to evaluate the clinicopathologic features and histologic spectrum and to determine features that are helpful in distinguishing benign from malignant cystic adrenal tumors. RESULTS. A total of 41 cases of macroscopically cystic lesions among patients who underwent surgery at the Mayo Clinic were identified over a 25-year period. Of these 41 cases, 32 were pseudocysts, 8 were endothelial cysts, and 1 was an epithelial cyst. Of the 32 pseudocysts, 6 were associated with adrenal neoplasms, including 2 adrenal cortical carcinomas, 2 adrenal cortical adenomas, and 2 pheochromocytomas. One pheochromocytoma case was identified in association with an endothelial cyst. Both patients with cystic adrenal cortical carcinomas died of disease. CONCLUSIONS. Adrenal neoplasms, including adrenal cortical carcinomas, may be associated with benign-appearing cysts. Extensive pathologic sampling of resected tissues is important to rule out malignancy in patients with cystic adrenal lesions.