AB031. Endoscopic transsphenoidal surgery for functional pituitary adenoma: shifting paradigms towards pseudocapsule-based resection.

ABSTRACT

BACKGROUND: Functional pituitary adenomas (PAs) manifest as intricate clinical syndromes, and surgery emerges as the principal intervention to mitigate associated morbidity and mortality. The endoscopic transsphenoidal surgery (ETS) approach stands as the preferred method for addressing PAs, with postoperative remission acting as a pivotal prognostic factor. METHODS: This study seeks to evaluate the influence of different surgical techniques and complications of ETS on functional PAs, focusing on both Acromegaly and Cushing's disease (CD). Patient records, including characteristics, perioperative assessments, postoperative complications, and follow-up data, were systematically gathered. Tumor resection methods were categorized into (I) complete pseudocapsule resection; and (II) complete piecemeal resection. Post-surgery, daily monitoring of serum cortisol levels continued for a consecutive 3-day period until values of 2 µg/dL or less were achieved. Growth hormone levels were reassessed 12 weeks later, targeting a level of <0.14 g/L. A follow-up enhanced magnetic resonance imaging examination was conducted 3 months post-surgery to confirm the absence of residual tumors. RESULTS: The study identified 46 patients (23 with acromegaly and 13 with CD) who underwent endoscopic surgery between 2020 and 2023. Twenty-six patients underwent piecemeal resection (January 2020 to December 2022), while 10 patients underwent complete pseudocapsule removal (January to December 2023). No significant changes in surgical complications were observed between the two techniques. No instances of carotid artery injury, epistaxis, intracranial infection, or loss of olfaction were reported. In the pseudocapsule group, one patient experienced transient vision loss. Notably, 80% of patients in the pseudocapsule group achieved remission as compared to 57.7% in the piecemeal group. CONCLUSIONS: Pseudocapsule-based resection exhibited a remarkable remission rate, a low complication rate, and an absence of recurrence in functional adenoma patients. Despite the limited number of cases and our early experience, further studies are warranted to validate its effectiveness and safety.