The generous application of CT discloses a great deal of unsuspected and usually innocuous masses. Adrenal masses are identified in 0.06% of the general population; although most are of no significance, the chance finding of a silent but significant adrenal tumor must be seized by evaluation.

The adrenal gland is a common site for metastatic disease, and this diagnosis should be strongly entertained in patients with bilateral masses or a history of cancer. Primary tumors of the adrenal cortex include adenomas, carcinomas, and myelolipomas. They may be functional with excess hormonal status or without function. The adrenal medulla may develop neuroblastoma, neuroganglioma, or (in adults) pheochromocytoma. Pheochromocytoma may be malignant or benign.

The first test is to rule out pheochromocytoma even if the patient has no clinical manifestations of catecholamine excess. Testing also should include cortical hormone testing for cortisol. If the tumor has no endocrine activity and there is a suspicion of metastatic disease, a CT-guided needle biopsy may clarify the situation.

If the tumor has no endocrine activity and is less than 3 cm in diameter, the patient may be followed with repeat CT at 6 months and again at 1 year. If endocrine activity is discovered, resection is indicated. Tumors smaller than 3 cm are quite unlikely to represent malignant disease, and expectant management is safe. For tumors larger than 5 cm, resection is the treatment of choice, regardless of secretory status. The probability of malignancy climbs into the clearly finite range of some 10%, and expectant management is not reasonable. If the tumor is between 3 and 5 cm, there is not a clear answer as to the best management, and the next steps must be considered in light of the patient’s informed consent and overall health management.

The superior adrenal artery is a branch of the inferior phrenic artery; the middle adrenal artery arises directly from the aorta; and the inferior adrenal artery branches from the renal artery. Venous drainage on the right is directly into the vena cava, and this vein can be treacherously short. Venous drainage on the left is into the renal vein.

Even though the history of breast cancer is distant, CT-guided needle biopsy of the adrenal gland is appropriate. Needle biopsy is not particularly useful to distinguish benign from malignant adrenal tumors, and needle biopsy of a pheochromocytoma is dangerous in that a catastrophic release of catecholamine may occur. Needle biopsy should probably be reserved for cases of possible metastatic disease.

Adrenalectomy is strongly recommended if this is consistent with overall patient management. A tumor of 5 cm may be resected by laparoscopy or laparotomy or through a retroperitoneal approach. Laparoscopy becomes problematic when the gland is large and when the tumor is malignant with uncertain invasion of surrounding tissue. The recommendation of laparotomy to explore has lost impetus, and advanced imaging techniques such as spiral CT, even with tumors that have a strong likelihood of bilaterally such as pheochromocytoma, have come into favor. The posterior approach offers no advantage over laparoscopy, which may become the preferred operation for all small adrenal tumors.

Follow the laparoscopy with physical examination and CT every 2 years. The histology of adrenal cortical tumors is not sufficiently precise to absolutely differentiate between cortical adenomas and carcinoma. Occasionally, only malignant behavior such as local or distant metastasis declares a tumor to be a cancer.