Adrenal Disorders Incidentalomas

With improvements in the resolution and availability of abdominal scanning (i.e., CT, MRI, and USG), many small tumors are being found in the adrenal glands incidentally—i.e. when the scan is performed during the work-up for another reason. Up to 5% of patients undergoing an abdominal CT scan will have a small adrenal mass. Most of these incidentalomas are hormonally inactive:

• 55% are nonfunctioning, benign adenomas
• 20% are a metastasis from another primary cancer, such as breast, lung, kidney, melanoma, or lymphoma
• 5% are a primary adrenal cancer
• 20% are a hormone producing tumor—i.e., a cortisol producing tumor, an aldosteronoma, or a pheochromocytoma

A tumor with a mass of 5 cm or larger has a greater likelihood of being malignant.

Diagnosis

The work up of an incidental mass discovered through abdominal imaging begins by evaluating the patient for signs and symptoms of hormone overproduction. The treatment for incidentalomas depends on 2 major factors: 1) whether or not the tumor is making excess hormone and 2) the chance of the tumor being cancer. These two factors are determined by obtaining the screening blood and urine tests previously outlined, as well as a CT or MRI scan. It is vitally important to exclude the possibility of pheochromocytoma prior to operating (on any part of the body for any indication), since surgery on unprepared patients with pheochromocytoma can be fatal.

Treatment

Functioning adrenal tumors should be surgically removed to eliminate the source of the excess hormone production. Patients with a nonfunctioning adrenal mass that is less than 3 cm should be followed by abdominal imaging every six months. The likelihood of an adrenal tumor being a cancer is heavily dependent on the tumor size. Once a tumor has reached 5 cm, the risk of developing cancer outweighs the risks of surgical removal. Tumors that are 5 cm or greater, or that are rapidly growing should, therefore, be surgically removed. Typically the surgery can be performed laparoscopically, through several very small incisions. Tumors that are between 3 cm and 5 cm may be either removed or observed depending on the patient's overall health and preferences.