2026 Proffered Presentations
S258: CLINICAL IMPACT OF PSEUDOCAPSULE DISSECTION ON EARLY CORTISOL SUPPRESSION AND LENGTH OF STAY IN CUSHING'S DISEASE
Jared Chung, BS1; Georgios Maragkos, MD2; Georgios Mantziaris, MD2; Gregory Hong, MD3; Erica Giraldi, MD3; Michael Catalino, MD2; Yamini Sterrett, MD4; John Jane Jr, MD5; 1University of Virginia School of Medicine; 2University of Virginia Department of Neurosurgery; 3University of Virginia Department of Endocrinology; 4Carilion Clinic Department of Endocrinology; 5Carilion Clinic Department of Neurosurgery
Introduction: Early postoperative cortisol decline is a critical marker of biochemical remission in Cushing’s disease and achievement of nadir cortisol <2 µg/dL is a well-established predictor of long-term outcomes. The pseudocapsule surrounding ACTH-secreting adenomas provides a natural surgical plane, but the relationship between extent of pseudocapsule dissection and likelihood of achieving nadir <2 after transsphenoidal surgery (TSS) remains unclear.
Objective: To determine the relationship between extensive pseudocapsule dissection and postoperative nadir cortisol decline.
Methods: We retrospectively reviewed 81 pathology-positive patients undergoing TSS for Cushing’s disease between 2017 and 2024. Serum cortisol was measured every 6 hours postoperatively until nadir or <1 µg/dL. Dissections were classified as complete (all six walls intact), near-total (all walls with capsule breach), majority (4–5 walls), partial (2–3 walls), piecemeal (0–1 wall), or subtotal hypophysectomy (STH) and collapsed into Group A (≥4 walls dissected), Group B (<3 walls), and Group C (STH). Outcomes included POD1 cortisol <2 µg/dL, hospital-stay nadir <2 µg/dL, and time to nadir (number of 6-hour draws). Kaplan–Meier analysis assessed suppression rates, with subgroup analyses for microadenomas and MRI-positive tumors.
Results: On POD1, 41/81 (50.6%) patients had cortisol <2 µg/dL, and by discharge, 70/81 (86.4%) reached a nadir cortisol <2 µg/dL. Both the six-type (p = 0.008) and three-group (p = 0.016) pseudocapsule classification system predicted POD1 cortisol <2 µg/dL.
Beyond nadir <2, pseudocapsule dissection type also influenced the rate of suppression. Patients with complete, near-total, and majority dissections required fewer postoperative 6-hour draws to reach nadir cortisol (4.0 [3.0, 6.0], 3.0 [3.0, 4.0], and 5.0 [4.0, 6.5], respectively) compared to partial (6.0 [5.0, 8.0]) and piecemeal (6.5 [4.5, 10.0]) dissections (p = 0.002). Cases of STH reached a nadir with an average of 6.0 [4.0, 10.0] draws. Subgroup analyses of microadenomas (p = 0.003) and MRI-positive tumors (p < 0.001) demonstrated the same pattern.
When combined into groups, Group A tumors demonstrated a significantly faster time to nadir compared to Groups B and C (p = 0.016). This effect remained significant within microadenomas (p = 0.014) and MRI-positive tumors (p < 0.001), suggesting that the impact of more extensive pseudocapsule dissection on early suppression is independent of tumor size or radiographic visibility.
Importantly, while achieving nadir <2 µg/dL itself did not correlate with hospitalization time (p = 0.60), time to nadir significantly predicted shorter length of stay (p = 0.002). This demonstrates that the speed of biochemical suppression, shaped by pseudocapsule dissection, carries practical value by reducing monitoring requirements and inpatient resource utilization.
Conclusion: Extent of pseudocapsule dissection predicts achievement of nadir cortisol <2 µg/dL. More extensive pseudocapsule dissection accelerated suppression, shortened time to nadir, and correlated with reduced hospital length of stay. These findings highlight pseudocapsule-guided dissection as both a surgical strategy and a means of optimizing perioperative care.