Despite the growing application of endoscopic transsphenoidal surgery (ETSS), outcomes for GH adenomas are not clearly defined.

We reviewed our experience with ETSS with specific interest in remission rates using the 2010 consensus criteria, predictors of remission, and associated complications.

This was a retrospective single institution study.

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.

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.

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.