Endoscopic Endonasal Approach to the Growth Hormone–Secreting Pituitary Adenomas: Endocrinologic Outcome in 68 Patients

Abstract

The endoscopic endonasal approach has recently become an acceptable option for resection of all pituitary adenomas. We assessed biochemical outcome of endoscopic endonasal surgery in growth hormone (GH)-secreting adenomas, including remission rate, predictors of remission, and associated complications. Sixty-eight consecutive patients with acromegaly who underwent endoscopic endonasal surgery were analyzed prospectively. Tumors were classified according to size, Knosp grade, and Hardy-Wilson classification. Biochemical remission was defined as normal serum insulin-like growth factor 1 level and either a suppressed GH serum level less than 0.4 μg/L during an oral glucose tolerance test or a random GH level less than 1.0 μg/L at least 3 months after surgery. Total biochemical remission rate was 64.7%. Gross total resection was achieved in 61 of the 68 patients (89.7%). Remission was achieved in 12 of 16 microadenomas (75%) and 32 of 52 macroadenomas (61.5%). Based on univariate logistic regression analysis, preoperative variables predictive of remission were age (P=0.004), Knosp grade (P= 0.023), and preoperative GH levels (P= 0.042). Three patients (4.4%) experienced postoperative panhypopituitarism, and permanent diabetes insipidus was seen in 4 patients (5.9%). Two patients (2.9%) developed cerebrospinal fluid leaks, which were treated by lumbar puncture in one case and early surgical repair in the other case. Endoscopic endonasal adenoma resection leads to a high rate of endocrinologic remission in GH-secreting adenomas with a low complication rate. Patients with older age, higher preoperative GH levels, and higher Knosp grades are less likely to achieve remission.