Glucocorticoid replacement therapy after retroperitoneal laparoscopic unilateral adrenal adenoma resection in patients with non-cortisol secreting tumors: a retrospective cohort study.

Background: Adrenal Cushing's syndrome is caused by an adrenal tumor that produces hypercortisolism and requires glucocorticoid supplementation following resection of the tumour to prevent adrenal insufficiency. Few studies have examined whether glucocorticoid replacement (GR) therapy is required after retroperitoneal laparoscopic unilateral adrenal adenoma resection in patients with non-cortisol secreting tumors, or whether there is any correlation between preoperative biochemical indicators and postoperative cortisol function. This study sought to investigate which patients with non-cortisol secreting tumors required GR therapy after undergoing retroperitoneal laparoscopic resection of unilateral adrenal cortical adenoma.

Methods: This retrospective case-control study included patients who underwent unilateral adrenalectomy, and who had a postoperative pathological diagnosis of adrenal cortical adenoma. Including primary aldosteronism and non-functional adrenal adenoma. In total, 35 patients were included in the study, of whom 12 were male and 23 were female. All the patients successfully underwent retroperitoneal laparoscopy. The adrenal adenoma resection patients were divided into the following two groups based on whether they received GR therapy after surgery: (I) the no GR group, which comprised 28 patients; and (II) the GR group, which comprised 7 patients. Routine preoperative, adrenal-related, basal serum cortisol, and plasma adrenocorticotropic hormone (ACTH) tests were conducted, and the percentage of eosinophils, and the number of eosinophils were assessed each morning for 3 days after surgery. Repeated measures analysis of variance was used, and the F value was the main statistic used to test for differences between groups, which was used to evaluate the magnitude of differences between groups.

Results: Before surgery, except for the ACTH level which showed a statistically significant difference between the two groups (P=0.04), there were no statistically significant differences between the two groups (P>0.05) in terms of eosinophil percentage, eosinophil count, serum potassium level, serum sodium level, cortisol levels (8 am, 4 pm, 12 am), and renin-angiotensin II-aldosterone levels (recumbent/standing), among others. After surgery, there were significant differences between the two groups in terms of the morning basal serum cortisol level (at 8 am) and the ACTH level (F=25.037, P<0.001; F=12.033, P=0.001), but no significant differences in the percentage and number of eosinophils were observed between the two groups. After laparoscopic adrenal adenoma resection, patients' cortisol levels are low on the first postoperative day, but most adrenal cortisol levels respond well to ACTH stimulation. On the second and third days after surgery, patients' cortisol levels generally return to normal without GR therapy. However, for patients with continuously low levels of cortisol and ACTH 3 days after surgery, supplemental glucocorticoids should be actively given in the early postoperative stage.

Conclusions: This study preliminarily showed that postoperative cortisol and ACTH levels can be used to identify patients at an increased risk of hypocortisolism after unilateral adrenal adenoma surgery, and to guide the use of GR therapy.