Biochemical assessment of adrenal insufficiency after adrenalectomy for non-cortisol secreting tumors: clinical correlation and recommendations

Background Data regarding changes in cortisol axis after adrenalectomy for non-cortisol secreting tumors and their correlation with adrenal insufficiency are limited. Our aim was to analyze these changes and their clinical correlations to guide management after adrenalectomy for non-Cushing’s tumors. Methods Following IRB approval, postoperative cortisol axis changes were analyzed in patients who underwent unilateral adrenalectomy for non-Cushing’s tumors. A morning serum cortisol of ≥ 10 μg/dl was accepted as a sufficient adrenal response. Results 223 adrenalectomies were analyzed. In 63% of patients, POD1 serum cortisol was ≥ 10 μg/dl and in 37% < 10 μg/dl. No patient with a POD1 cortisol ≥ 10 μg/dl developed AI symptoms, whereas symptoms of AI were observed in 4% of those with < 10 μg/dl. In patients with a POD1 cortisol of < 10 μg/dl, the rate of steroid replacement therapy initiation was 100%, 8%, and 25% when the decision was based on serum cortisol, clinical symptoms, and serum cortisol plus ACTH stimulation test results, respectively. In 90% of asymptomatic patients, hypocortisolemia resolved uneventfully within a week on repeat morning cortisol testing. 75% of patients with hypocortisolemia on POD1 demonstrated an adequate cortisol response to ACTH stimulation test. Conclusion Although postoperative hypocortisolemia was observed in 37% of patients undergoing unilateral adrenalectomy for non-cortisol secreting tumors, majority did not develop symptoms of adrenal insufficiency. All three steroid initiation approaches appeared safe, with management based on clinical symptoms or selective ACTH stimulation testing sparing more patients from steroids compared to steroid initiation based on POD 1 cortisol levels alone.