Abstract: Objective To investigate the clinical efficacy of endoscopic transsphenoidal surgery in the treatment of non-invasive growth hormone(GH)-secreting pituitary adenoma, and to analyze the predictive value of postoperative GH and insulin-like growth factor-1(IGF-1)levels for long-term hormonal biochemical remission. Methods The clinical data of 38 patients with non-invasive GH-secreting pituitary adenoma who underwent endoscopic transsphenoidal surgery at our institution from October 2012 to August 2024 were retrospectively collected and factors influencing long-term remission were analyzed. Receiver operating characteristic(ROC)curves were used to evaluate the predictive performance of GH and IGF-1 levels on the postoperative day 1, as well as the postoperative IGF-1/preoperative IGF-1 ratio. Results Among the 38 patients included in the study,26 achieved long-term biochemical remission, with a remission rate of 68.4%. Compared to the non-remission group, the remission group had significantly lower GH levels(P<0.001), IGF-1 levels(P=0.026)on the postoperative day 1, and a lower postoperative IGF-1/preoperative IGF-1 ratio(P=0.003). ROC analysis revealed that the area under the curve(AUC)for postoperative GH, IGF-1, and the IGF-1 ratio were 0.904, 0.789, and 0.839, respectively. A postoperative GH level of <1.66 ng/mL was found to predict long-term remission with a sensitivity of 91.7% and a specificity of 84.6%, while a postoperative IGF-1/preoperative IGF-1 ratio of <75.8% was found to predict remission with a sensitivity of 75.0% and a specificity of 85.7%. Conclusion The endoscopic transsphenoidal surgery is an effective treatment for non-invasive GH-secreting pituitary adenoma. Patients exhibiting lower postoperative GH and IGF-1 levels, as well as a lower postoperative IGF-1/ preoperative IGF-1 ratio, are more likely to achieve long-term biochemical remission. Of these, postoperative GH levels demonstrated the highest predictive value.

Key words: Growth hormone-secreting pituitary adenoma, Growth hormone, Insulin-like growth factor-1, Endoscopic surgery, Long-term remission