Adrenal Schwannoma: A Very Rare Cause of Adrenal Incidentaloma

An adrenal incidentaloma is an adrenal mass, usually ≥1cm in diameter, and discovered during a radiologic examination performed for indications other than an evaluation for adrenal disease (1,2). The prevalence of adrenal incidentalomas was found to be 4% on abdominal ultrasound imaging performed for an unrelated reason. In post-mortem studies, the prevalence of adrenal masses smaller than 1 cm was reported to be 65% (3,4). Adrenal incidentalomas can be either benign or malignant. Among the benign lesions, adenoma, pheochromocytoma, myelolipoma, and adrenal hyperplasia are the most common ones while the adrenal schwannomas are seen extremely rarely. In a study from Canada, 381.200 adrenal incidentaloma specimens were analyzed and adrenal schwannoma was detected in only one case (5). Schwannomas are generally well circumscribed, solitary, and encapsulated tumors. Although they are observed between the ages of 22 and 55 years in most cases, they can be seen at any age. Both sexes are affected equally. Most typically, they grow slowly. In addition, clinical findings of retroperitoneal schwannomas occur late because of the anatomical localization of the tumor (6,7). Here, were present a case of schwannoma as a very rare cause of adrenal incidentalomas.