A 53-year-old man was referred to the authors’ hospital with an 8-month history of bilateral gynecomastia and decreased libido for which he was treated with tamoxifen 20 mg/d. Five months later, he experienced abdominal pain accompanied by nausea and headache. He also reported weight loss of approximately 5 kg. An abdominal echogram revealed the presence of a 10-cm mass in contact with the superior pole of the right kidney and partial compression of the inferior vena cava. The hormonal evaluation showed an increased serum estradiol as the only abnormality. Computed tomography scan confirmed the echographic findings. The patient underwent right adrenalectomy and, with the diagnosis of adrenal carcinoma, was treated with mitotane. During treatment, adrenal insufficiency and primary hypogonadism developed. Although he recovered gonadal function after mitotane was discontinued, adrenal insufficiency persisted. There was no clinical evidence of the disease 11 years after the surgical resection of the mass.