Bilateral Testicular Tumors Resulting in Recurrent Cushing Disease After Bilateral Adrenalectomy

Context: Recurrence of hypercortisolism in patients after bilateral adrenalectomy for Cushing disease is extremely rare. Patient: We present a 27-year-old man who previously underwent bilateral adrenalectomy for Cushing disease with complete clinical resolution. Cushingoid features recurred 12 years later, with bilateral testicular enlargement. Hormonal tests confirmed adrenocorticotropic hormone (ACTH)-dependent Cushing disease. Surgical resection of the testicular tumors led to clinical and biochemical remission. Design and Results: Gene expression analysis of the tumor tissue by quantitative polymerase chain reaction showed high expression of all key steroidogenic enzymes. Adrenocortical-specific genes were 5.1 x 105 (CYP11B1), 1.8 x 102 (CYP11B2), and 6.3 x 104 (MC2R) times higher than nonsteroidogenic fibroblast control. This correlated with urine steroid metabolome profiling showing 2 fivefold increases in the excretion of the metabolites of 11-deoxycortisol, 21-deoxycortisol, and total glucocorticoids. Leydig-specific genes were 4.3 x 101 (LHCGR) and 9.3 x 100 (HSD17B3) times higher than control, and urinary steroid profiling showed twofold increased excretion of the major androgen metabolites androsterone and etiocholanolone. These distinctly increased steroid metabolites were suppressed by dexamethasone but unresponsive to human chorionic gonadotropin stimulation, supporting the role of ACTH, but not luteinizing hormone, in regulating tumor-specific steroid excess. Conclusion: We report bilateral testicular tumors occurring in a patient with recurrent Cushing disease 12 years after bilateral adrenalectomy. Using mRNA expression analysis and steroid metabolome profiling, the tumors demonstrated both adrenocortical and gonadal steroidogenic properties, similar to testicular adrenal rest tumors found in patients with congenital adrenal hyperplasia, suggesting the presence of pluripotent cells even in patients without congenital adrenal hyperplasia