Management of Cushing's Disease: Changing Trend from Microscopic to Endoscopic Surgery

BACKGROUND: Cushing's disease (CD) is a spectrum of clinical manifestations due to adrenocorticotropic hormone-secreting pituitary adenoma. Transsphenoidal adenomectomy remains the standard treatment. There has been a paradigm shift from microscopic to endoscopic transsphenoidal surgery in recent years. However, the efficacy of endoscopic transsphenoidal surgery has not been established. Therefore, it is of interest to determine the superiority of endoscopic transsphenoidal surgery, if any, over microscopic surgery. OBJECTIVE: To assess the efficacy of endoscopic endonasal transsphenoidal surgery for the treatment of CD and to determine the factors affecting remission. METHODS: Patients undergoing surgery for CD from 2009 to 2017 were analyzed retrospectively. Transsphenoidal resection was the preferred treatment, with recent trends in favor of the endonasal endoscopic skull base approach. Postoperative cortisol level of <2 mu g/dL was taken as remission and value between 2 and 5 mu g/dL as possible remission. RESULTS: In total, 104 patients operated primarily for CD were included for analysis; 47 patients underwent microscopic surgery, 55 endoscopic surgery, and 2 were operated transcranially. Remission was achieved in 76.47% of patients. In univariate analysis, factors significantly associated with remission were 1) type of surgery (P = 0.01); remission in endoscopy surgery (88.23%) is better than microscopy (56.6%); 2) postoperative day 1 morning cortisol (P = 0.004); and 3) postoperative day 1 morning ACTH (P = 0.015). In multivariate analysis, only postoperative day 1 cortisol was found to be significant predictor of remission (P = 0.02). CONCLUSIONS: Postoperative plasma cortisol level is a strong independent predictor of remission. Remission provided by endoscopy is significantly better than the microscopic approach.