Gynecomastia in a Man With Adrenal Mass.

Estrogen-secreting adrenocortical carcinoma (ACC) is exceedingly rare, representing 1% to 2% of all ACCs. We present a case of a 65-year-old man diagnosed with an estrogen-secreting, 4.3-cm right adrenal mass discovered during work-up for bilateral gynecomastia. Gynecomastia and hyperestrogenism resolved after laparoscopic adrenalectomy, and pathology was reported as adrenocortical adenoma. However, 5 years later, he again developed bilateral gynecomastia because of recurrent hyperestrogenism. Imaging revealed multiple metastases in the abdomen. Urine steroid profiling demonstrated increased androgen precursors, androgen metabolites, and glucocorticoid precursors. Ultrasound-guided biopsy of one of the metastases confirmed ACC. Initial therapy included debulking surgery with removal of metastatic lesions. Mitotane therapy was initiated 4 weeks later along with hydrocortisone for anticipated mitotane-induced adrenal insufficiency. Histopathology from the adrenalectomy specimen 5 years earlier was rereviewed and confirmed ACC. Estrogen-secreting adrenal tumors are exceedingly rare, and the majority are malignant. This case underlines the importance of making an initial accurate diagnosis of adrenal malignancy that allows better surgical planning and appropriate monitoring. Indeterminate imaging characteristics of the adrenal mass, as well as the presentation with estrogen excess, suggested an elevated risk for ACC. Initial pathology-based misdiagnosis illustrates the need for an expert adrenal pathologist to review these rare tumors.