Massive adrenal incidentalomas and late diagnosis of congenital adrenal hyperplasia in prostate cancer

In a 61-year-old Caucasian male with prostate cancer, leuprolide and bicalutamide failed to suppress the androgens. He presented to endocrinology with persistently normal testosterone and incidental massive (up to 18 cm) bilateral adrenal myelolipomas on CT scan. Blood test did not reveal metanephrine excess. The patient was noted to have short stature (151 cm) and primary infertility. Elementary school photographs demonstrated precocious puberty. Physical examination revealed palpable abdominal (adrenal) masses. Abiraterone and glucocorticoid treatment was commenced with excellent suppression of testosterone. Genetic testing revealed a mutation in CYP21A2 confirming 21-hydroxylase-deficient congenital adrenal hyperplasia (CAH). Association of large myelolipomas with CAH has been reported in the literature. Our case highlights the importance of considering CAH in patients with non-suppressed testosterone despite androgen deprivation therapy. Large myelolipomas should raise the suspicion of congenital adrenal hyperplasia. LEARNING POINTS: Adrenal myelolipomas are rare benign lesions that are more common in patients with longstanding untreated congenital adrenal hyperplasia thought to be due to ACTH stimulation. Consider undiagnosed congenital adrenal hyperplasia in patients with adrenal myelolipoma. Glucocorticoid replacement may be an efficacious treatment for patients with prostate cancer and CAH. Abiraterone therapy has a risk of adrenal crisis if glucocorticoids are not replaced.