Adenomatoid tumor of the adrenal gland with micronodular adrenal cortical hyperplasia.

We report a case of an adenomatoid tumor (AT) of an adrenal gland with micronodular adrenal cortical hyperplasia (ACH). A 51-year-old man was found to have newly developed hypertension with clinical evidence of primary aldosteronism. A computerized tomogram of the abdomen revealed a solitary mass in the right adrenal gland. He underwent a right adrenalectomy for a presumptive clinical diagnosis of a solitary aldosterone-producing adrenal cortical adenoma. On histopathologic examination, the adrenal gland demonstrated an AT, diagnosed by the characteristic histological features, immunohistochemical stain results, and electron microscopic findings. The surrounding adrenal cortex showed multiple small hyperplastic cortical nodules. After the adrenalectomy, the patient's blood pressure normalized. Primary AT of the adrenal gland coexisting with micronodular ACH associated with hypertension has not been previously reported.