Endoscopic Transsphenoidal Surgery for Acromegaly: Remission Using Modern Criteria, Complications, and Predictors of Outcome

Context: Despite the growing application of endoscopic transsphenoidal surgery (ETSS), outcomes for GH adenomas are not clearly defined. Objective: We reviewed our experience with ETSS with specific interest in remission rates using the 2010 consensus criteria, predictors of remission, and associated complications. Design and Setting: This was a retrospective single institution study. Patients, Interventions, and Outcome Measures: Sixty acromegalic patients who underwent ETSS were identified. Remission was defined as a normal IGF-I and either a suppressed GH less than 0.4 ng/ml during an oral glucose tolerance test or a random GH less than 1.0 ng/ml. Results: Remission was achieved in all 14 microadenomas and 28 of 46 macroadenomas (61%). Tumor size, age, gender, and history of prior surgery were not predictive on multivariant analysis. In hospital postoperative morning GH levels less than 2.5 ng/ml provided the best prediction of remission (P < 0.001). Preoperative variables predictive of remission included Knosp score (P = 0.017), IGF-I (P = 0.030), and GH (P = 0.042) levels. New endocrinopathy consisted of diabetes insipidus in 5%, adrenal insufficiency in 5.4%, and new hypogonadism in 29% of men and 17% of women. However, 41% of hypogonadal men had normal postoperative testosterone levels and 83% of amenorrheic women regained menses. The most common complaints after surgery were sinonasal (36 of 60, 60%) resolving in all but two. Conclusions: ETSS for GH adenomas is associated with high rates of remission and a low incidence of new endocrinopathy. Despite the panoramic views offered by the endoscope, invasive tumors continue to have lower rates of remission. (J Clin Endocrinol Metab 96: 2732-2740, 2011)