Adrenal Gland Transplants Show Long-term Efficacy in Refractory Cushing’s Disease, Study Reports
Adrenal gland transplants resulted in complete resolution of Cushing’s disease symptoms after no long-lasting benefits were seen with pituitary surgery, according to a new long-term study in four patients.
The procedure also enabled lower doses of hormone replacement therapy, the findings showed.
The research, “Autologous Adrenal Transplantation for the Treatment of Refractory Cushing’s Disease,” was published in the journal Urologia Internationalis.
When pituitary surgery fails to improve Cushing’s disease symptoms, one option is to remove both adrenal glands, which stops cortisol from being produced. One problem with that approach, however, is that patients then require hormone replacement therapy for the rest of their lives. They also may be at risk of complications such as Nelson’s syndrome, characterized by an enlarged pituitary gland and the development of large and invasive growths known as adenomas.
By preserving glucocorticoid levels, autologous adrenal gland transplantation — which uses the body’s own — may be a way to prevent the development of such complications. It also may reduce the need for hormone replacement treatments after bilateral adrenalectomy, or adrenal gland removal.
A team with the Peking Union Medical College Hospital reported on four people with Cushing’s disease (three women; mean age 30 years) who underwent this procedure after relapsing within 6-12 months of transsphenoidal surgery to remove the pituitary tumor. One of these patients received pituitary radiotherapy one year after the surgery, with no clinical improvement.
All underwent right followed by left adrenalectomy, half of the surgeries using endoscopy. The adrenal membrane was kept intact. During transplantation, an adrenal graft was implanted into the left iliac fossa — located in the internal surface of the ilium, part of the hip bone — with surgical connections called anastomoses.
Follow-up evaluations were conducted up to 10 years after surgery in two patients, while the other two were lost to follow-up after one year. Hormone replacement dosage was guided by clinical symptoms and levels of serum cortisol, urinary-free cortisol, and adrenocorticotrophic hormone (ACTH).
At the most recent follow-up, all four patients were on lower doses of hormone replacement than physiologically necessary — indicating functional adrenal glands, the investigators said. Still, the fact that the patients needed hormone replacement made the researchers recommend increasing the mass of the autograft.
Serum cortisol levels decreased one week post-transplantation in all patients, then progressively increased throughout follow-up, though not reaching pre-surgery levels. As for ACTH, one patient showed a decrease to undetectable levels at three months, while another saw a reduction to normal range within one year, but exceeded pre-surgery level at 10 years. The two patients with shorter follow-up showed mild increases in ACTH amounts at one year.
Hormone replacement doses were stable in all four individuals at their last evaluation. Three were started on 10 mg prednisone immediately after transplantation, and all four were on hydrocortisone one year later. Among the two people with longer follow-up durations, one was maintained on 20 mg hydrocortisone, and the other on 5 mg prednisone. Taking prednisone or hydrocortisone was not associated with differences in serum hormone levels.
Hypertension, or high blood pressure, and hypokalemia, which is low serum potassium, resolved within 1-3 days of surgery. Moon faces and “buffalo hump” — a fat lump between the shoulders — two characteristic Cushing’s disease symptoms, resolved within six months.
None of the patients developed Nelson’s syndrome. One individual showed skin hyperpigmentation, while another experienced seizures after pituitary surgery. The seizures likely were due to anterior pituitary dysfunction, the team said.
“In this series of 4 patients, we demonstrate the long-term efficacy of bilateral adrenalectomy with autologous adrenal transplantation and propose this procedure as a viable treatment option for refractory Cushing’s disease,” the investigators said.