Benign vascular tumors, cysts, and pseudocysts of the adrenal gland: a contemporary multi-institutional clinicopathological analysis of 55 cases.

Benign adrenal vascular tumors, cysts, and pseudocysts are a heterogeneous group of relatively uncommon entities that may pose diagnostic challenges radiologically and pathologically. However, there are only a few small cases series systematically characterizing the clinicopathological features of these lesions. We identified 55 cases of benign adrenal vascular tumors, cysts, and pseudocysts (23 pseudocysts, 17 hemangiomas, 8 lymphangiomas, 6 angiomatous endothelial cysts, and 1 arteriovenous malformation) from a multi-institutional urologic pathology database between 2000 and 2017 and retrospectively analyzed their clinicopathological features. We found that these lesions have a female predominance and most are right sided. These lesions may occur simultaneously with other adrenal tumors associated with hormonal hypersecretion. A substantial portion of pseudocysts were semisolid or solid with no fluid collection, mimicking a solid adrenal tumor and resulting in adrenalectomy. In addition, a small proportion of benign vascular lesions may have coexisting epithelial tumors, requiring extensive specimen sampling and thorough microscopic examination.