A 30-Year, Single-Center Experience of Unilateral Adrenalectomy for Primary Bilateral Macronodular Adrenal Hyperplasia

Abstract

Objective: The aim was to assess the short- and long-term outcomes of unilateral adrenalectomy (UA) in patients with primary bilateral macronodular adrenal hyperplasia (PBMAH).

Methods: We conducted a retrospective study of 124 patients with PBMAH who underwent UA.

Results: One hundred sixteen patients were available for follow-up (median, 28.5 months). Cushingoid features remitted in 43 of 65 patients (70.8%) with overt Cushing syndrome (CS). Hypertension and diabetes mellitus improved in 79 of 96 (82.3%) and 29 of 42 patients (69.0%), respectively. Glucocorticoid insufficiency developed in 7 of 116 patients (6.0%) after the surgery, and it resolved in all the patients during follow-up. The mean 24-hour urinary free cortisol level decreased gradually from 456.02 ± 422.33 mg/24 h at baseline to 84.47 ± 70.06 mg/24 h within 3 months and then increased progressively in some patients. Sixty-four of the 116 patients (55.2%) had biochemical recurrence and 43 patients (67.2%) underwent contralateral adrenalectomy. The median time interval between the second operation and the first UA was 24 months. Patients with overt CS had a larger surgical-side or contralateral adrenal volume than patients without overt CS. Patients with a contralateral adrenal volume of >33.54 mL or with a preoperative urinary free cortisol level of >216.08 mg/24 h were more likely to have recurrence.

Conclusion: The efficiency of UA is transient for the majority of patients, and the indications should be strictly limited to those with subclinical or milder CS. Patients who undergo successful UA still require close life-time follow-up for the recurrence of hypercortisolism.

Keywords: Cushing syndrome (CS); adrenocorticotropin-independent macronodular adrenal hyperplasia (AIMAH); follow-up; primary bilateral macronodular adrenal hyperplasia (PBMAH); unilateral adrenalectomy (UA).