Diagnosis and treatment of the adrenal cyst.

Adrenal cysts, first described in 1670, typically presented with abdominal pain or palpable mass. In the modern era, incidentally identified adrenal cysts are commonplace, as imaging studies have become a mainstay in patient evaluation. The rubric of adrenal cysts comprises a broad differential diagnosis, rendering definitive diagnosis and subsequent management difficult. These cysts are categorized into four subtypes: endothelial, pseudocyst, epithelial, and parasitic. Endocrine workup should rule out functional status. Radiologic differentiation is helpful; however, imaging characteristics, such as hemorrhage in a pseudocyst, can confound identification of benign versus malignant lesions. Any functional lesion, potentially malignant lesion, or benign lesion more than 5 cm in diameter deserves surgical treatment. For small, benign lesions, conservative management is a viable option, although no surveillance protocols have been described.