Surgery for Adrenal Hypercortisolism (AHC): Adrenalectomy for High Cortisol and Cushing Syndrome

What is the Best Adrenal Operation for Cortisol-Producing Adrenal Tumors?

In our hands, the best operation for removing nearly all adrenal tumors that cause adrenal hypercortisolism (AHC) and Cushing Syndrome is the Mini Back Scope Adrenalectomy (MBSA). The operation is also called posterior retroperitoneoscopic adrenalectomy, because it is performed with very small scopes that go through the lower, outer back.

At our center, the Mini Back Scope Adrenalectomy (MBSA) is the preferred technique in more than 95% of adrenal operations, including nearly all operations for AHC. There are many reasons we prefer this technique. The operation is performed with a scope and three small incisions at the small of the patient's back. The cosmetic outcome is excellent. This provides a very direct approach to the adrenal gland. MBSA suits most tumors; very large tumors or known adrenal cancers may need a different approach. Dr. Carling has used this operative approach for many years, and the Carling Adrenal Center is one of the highest-volume adrenal surgery centers in the world.

How is a Mini Back Scope Adrenalectomy (MBSA) Performed? The way the operation is done, in experienced hands, typically leads to minimal blood loss. It is also faster, with less mobilization of the surrounding organs during the operation. All these factors lead to less pain for the patient, with a shorter length of stay, faster recovery, and faster return to normal activities and work. Less mobilization also means less risk of injury to surrounding structures such as the kidney, liver, spleen, pancreas, bowel, or major vessels such as the inferior vena cava (IVC).

Dr. Carling's Experience with AHC and Cushing Syndrome. Dr. Carling has performed thousands of adrenal operations over his career, including more than 2,400 since January 2022 alone, and he personally performs every operation. A Mini Back Scope Adrenalectomy (MBSA) typically takes 20 to 30 minutes. By going through the back the surgeon has a very direct approach to the adrenal gland. Dr. Carling adopted this technique while he was Chief of Endocrine Surgery at Yale University School of Medicine. Note that this is an advanced technique that most low-volume surgeons do not offer. The typical surgeon who performs adrenal surgery does about one adrenal operation per year, and outcomes are better with surgeons who do it regularly. If your surgeon plans to operate through the front of the abdomen to get to the adrenal gland located in the very back, consider a second opinion, and ask your surgeon how many adrenal operations they perform each year.

Who Should Have Adrenalectomy for AHC, Including Mild AHC (MACS)?

Adrenalectomy is the only cure for AHC. It is the first-line treatment whenever the tumor can be removed and the surgical risk is acceptable. Medication does not remove the tumor.

Severe AHC (overt adrenal Cushing syndrome) should be treated with surgery whenever feasible. In mild AHC (formerly MACS or subclinical Cushing syndrome) the decision is individualized. It is based on your cortisol-related health problems (high blood pressure, diabetes or prediabetes, osteoporosis or fractures, weight gain and others), whether one or both adrenal glands are involved, your age, your surgical risk and your preference. The higher the cortisol and the more of these problems you have, the stronger the case for surgery. Not every abnormal dexamethasone suppression test means an operation.

That said, we believe surgery is underused in AHC. Cortisol-related damage adds up over years and may be only partly reversible, so in our view “watch and wait” should not be the automatic choice. A randomized trial (CHIRACIC, Lancet Diabetes & Endocrinology 2025) found that adrenalectomy improved blood pressure control compared with conservative care in patients with MACS: the blood pressure goal was met in 46% of operated patients, compared with 15% of those managed without surgery. Read more in our blog post on surgery and high blood pressure, and about how AHC is graded on our diagnosis page.

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What are the Benefits of Surgery for AHC and Cushing Syndrome?

Adrenal tumor producing too much cortisol, causing adrenal hypercortisolism (AHC). The benefits are numerous. Adrenal surgery is the only curative therapy for AHC. Adrenalectomy leads to improvement in hypertension (high blood pressure) and, in many patients, in diabetes, body weight and dyslipidemia (poor blood fat levels), although the study results for these are less consistent than for blood pressure. In severe AHC (Cushing syndrome) we also see improvement in muscle weakness, bruising, wound healing, and emotional and neurocognitive function, and bone density usually improves. Within 6-12 months, many patients who have had surgery for Cushing syndrome describe themselves as a new person. Patients with Cushing syndrome have a greater risk of developing blood clots (venous thromboembolism, pulmonary embolism) around the time of surgery, and preventive blood-clot treatment is recommended. This is one more reason you want an experienced, safe, and efficient surgeon doing your adrenalectomy. An adrenalectomy that commonly takes 2 hours or more elsewhere typically takes Dr. Carling 20 to 30 minutes. There is no value in a fast operation, per se. However, a faster operation means less time under general anesthesia. Although general anesthesia is very safe, longer operations carry a greater risk of complications such as nausea, vomiting, blood clots, urinary retention (trouble emptying the bladder) and infections.

Steroid Replacement and Recovery after Adrenalectomy for AHC

While a tumor has been making too much cortisol, the pituitary and the remaining normal adrenal tissue have been suppressed (“asleep”), and they may need time to wake up after the tumor is removed. We test your cortisol the morning after surgery with a cosyntropin stimulation test, and steroid (hydrocortisone) replacement is given only if you need it. The need rises with the severity of the AHC: roughly 30–50% of patients with mild AHC, 50–100% with moderate AHC and nearly all patients with severe AHC need replacement for a time.

Recovery of the other adrenal gland takes months, and longer in severe disease. We will work with your endocrinologist so you have a clear plan for weaning off your hormone replacement after surgery.

Glucocorticoid withdrawal symptoms such as fatigue, muscle and joint aches, and low mood are common as your body readjusts to normal cortisol levels, even on the right replacement dose. They are temporary.

Is Medication an Alternative to Surgery for AHC?

Medicines can lower cortisol production (steroidogenesis inhibitors such as metyrapone and osilodrostat) or block the action of cortisol (the glucocorticoid-receptor blocker mifepristone). None of them removes the tumor, and they have to be taken for as long as the tumor is there. We see their role as a bridge to surgery, or for patients who cannot have surgery. For a patient with a removable adrenal tumor who is fit for an operation, we believe adrenalectomy is the better treatment.

What is the Treatment for AHC in Both Adrenal Glands (Bilateral Adrenal Tumors)?

Some patients have cortisol-producing tumors in both adrenal glands. These may be bilateral adenomas or primary bilateral macronodular adrenal hyperplasia (PBMAH), now also called bilateral macronodular adrenal cortical disease, which can be familial or sporadic. Primary pigmented nodular adrenocortical disease (PPNAD) is a different, micronodular condition (many very small nodules) that is usually hereditary. Adrenalectomy is the only potentially curative treatment. The Mini Back Scope Adrenalectomy (MBSA) is our preferred technique for both unilateral and bilateral AHC. Adrenal vein sampling is not recommended for cortisol disease. For bilateral adenomas and PBMAH, our preferred approach is staged, adrenal-sparing surgery (partial adrenalectomy): the two sides are operated on at least 6 weeks apart, the tumors are removed, and at least about 30% of one gland is preserved to avoid lifelong steroid dependence. Because the tissue that is left can form new nodules, follow-up cortisol testing is needed. In severe PPNAD, complete removal of both glands may be the better option. Patients with bilateral disease should have their operations performed at a high-volume adrenal surgery center. Read more about partial (adrenal-sparing) adrenalectomy. A complete bilateral adrenalectomy is rarely needed for AHC. When it has to be performed, it will inevitably cause permanent adrenal insufficiency requiring a lifelong mineralocorticoid and glucocorticoid replacement therapy. These patients require special attention and must have a booked follow up appointment with their endocrinologist before surgery. Patients and their family members need to know about adrenal insufficiency signs and symptoms including instructions on “sick day” dose adjustment and when and how to use emergency hydrocortisone injection. Patients should be provided with medical alert bracelets and hydrocortisone sodium succinate vials for emergency use. This is particularly important to understand, and we will work with your endocrinologist, so this is addressed prior to surgery.

What is the treatment for “failed” pituitary treatment of Cushing's Disease?

Cushing's disease is cortisol excess caused by a pituitary adenoma secreting ACTH; it is a different disease from AHC, where the adrenal gland itself is the source. It comprises a large spectrum of signs and symptoms that cause increased morbidity and mortality, and deterioration in quality of life. The first-line treatment option is surgical resection of the pituitary adenoma. However, up to about a third of patients with Cushing's disease will require a second treatment, either because the first pituitary surgery failed to control the cortisol excess or because it came back. Remember, too much cortisol is very harmful to the body. This is a big problem. Thus, the second-line treatment sometimes must be complete bilateral adrenalectomy. The goal is to stop the cortisol overproduction at its source. Bilateral adrenalectomy is an important treatment option when repeat pituitary surgery is no longer an option. The alternatives are radiation to the pituitary and long-term medication. Bilateral adrenalectomy controls the cortisol excess immediately and reliably, and improves quality of life. The Mini Back Scope Adrenalectomy (MBSA) is our preferred technique in “failed” Cushing's disease. A complete bilateral adrenalectomy inevitably causes permanent adrenal insufficiency requiring lifelong mineralocorticoid and glucocorticoid replacement therapy. As described above, these patients must have a follow-up appointment booked with their endocrinologist before surgery, and they and their family members need instructions on “sick day” dose adjustment, emergency hydrocortisone injection and a medical alert bracelet. After bilateral adrenalectomy for Cushing's disease, the pituitary tumor also needs continued follow-up, because it can grow. We will work with your endocrinologist so this is addressed prior to surgery.

Last updated October 2026.

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