Hormone outcomes following endoscopic endonasal resection of nonfunctional pituitary adenomas

OBJECTIVE Resection of nonfunctional pituitary adenomas (NFPAs) can precipitate transient, or in some cases, permanent hormone deficits requiring replacement. Predicting the risk of permanent hormone dysfunction and the possibility of improvement postsurgery is crucial for patient counseling. This study analyzed a large cohort of patients with NFPA to assess predictors of postoperative hormone function and to help both surgeons and patients better predict outcomes. METHODS The authors conducted a retrospective single-institution study on a series of patients treated for NFPAs at Weill Cornell Medicine between 2006 and 2023. Data including demographics, preoperative hormone status, laboratory values, pathological and radiographic tumor characteristics, and postoperative transient and permanent hormone replacement were collected. Multivariable logistic regression analysis was used to identify predictors of hormone deterioration and improvement. RESULTS A cohort of 372 patients were included in this study, 56% of whom presented with preoperative hormone deficiency of at least one axis. A total of 79% of patients underwent gross-total or near-total resection. Postoperatively, 178 (48%) required permanent hormone replacement for at least one hormonal axis: thyroid (34%), cortisol (23%), gonadotropin (15%), and antidiuretic hormone (7%). In patients with no preoperative endocrinopathy, 30.8% needed new hormone replacement therapy. Apoplexy and tumor size were strong predictors. If the tumor was < 2 cm, 23.5% needed new hormone replacement, and if the tumor was > 3 cm, 54.5% needed new hormone replacement. On the other hand, 39.5% of patients with a preoperative hormone deficiency did not require any long-term replacement. If the tumor was < 2 cm, 53.3% improved, and if the tumor was > 3 cm, 32.7% improved. Factors significantly associated with permanent hormone replacement and improvement besides tumor size and the presence of preoperative hormone deficiencies included hemorrhage on MRI, age, and sex, but these associated factors differed for each axis. CONCLUSIONS This study highlights the relatively high but balanced rates of hormone loss and improvement after surgical removal of nonhormone-producing adenomas. The size of the tumor, apoplexy, and the patient’s preoperative hormone status are strong predictors of outcome and can be used to estimate hormone function after surgery.