Predictors of glucocorticoid treatment intensity after endoscopic transsphenoidal surgery in patients with non-functional pituitary adenomas: a retrospective study.

BACKGROUND AND

OBJECTIVES

Non-functioning pituitary adenomas (NFPAs) are among the most common pituitary tumors, accounting for approximately 22-54% of all pituitary adenomas. Although histologically benign, NFPAs can cause considerable morbidity and mortality due to their potential to induce endocrine disturbances. Endoscopic transsphenoidal surgery (eTSS) is the preferred treatment modality; however, postoperative hypopituitarism-particularly adrenal insufficiency-is frequent, necessitating long-term glucocorticoid therapy. Determining the optimal glucocorticoid dosage remains a significant clinical challenge. This study aimed to identify independent predictors of postoperative glucocorticoid therapy intensity in NFPA patients by integrating imaging and endocrinological parameters, and to develop a predictive model that supports individualized glucocorticoid replacement therapy and optimizes clinical decision-making.

METHODS

This retrospective analysis included 116 patients who underwent pituitary adenoma resection between March 2019 and December 2024. Demographic, clinical, radiological, endocrinological, and pathological data were collected. Imaging assessments included tumor volume, pituitary stalk stretch, and suprasellar extension measured using 3D Slicer software. Preoperative serum cortisol and ACTH levels were determined. Multivariate regression analysis was performed to identify independent predictors of postoperative glucocorticoid therapy intensity.

RESULTS

Tumor volume, suprasellar extension, pituitary stalk stretch, and preoperative morning cortisol levels were identified as independent predictors of glucocorticoid therapy intensity (all p < 0.05), collectively explaining 72.1% of the variance (adjusted R 2 = 0.721). Bootstrap resampling confirmed model robustness (RMSE: 656.04; 95% CI: 637.50-690.22).

CONCLUSION

Tumor volume, suprasellar extension, pituitary stalk stretch, and morning cortisol level are key determinants of postoperative glucocorticoid therapy intensity in NFPA patients. The proposed model provides an evidence-based tool to optimize postoperative care, potentially reducing the risk of adrenal insufficiency and overtreatment.