Efficacy of Endoscopic Endonasal Transsphenoidal Surgery for Cushing’s Disease in 230 Patients with Positive and Negative MRI

Introduction

Cushing’s disease is a rare endocrine disorder caused by an excess production of cortisol due to a pituitary adenoma. Endoscopic endonasal transsphenoidal surgery (EETS) is the gold standard for tumor removal, but its effectiveness varies depending on MRI findings. This study evaluates the remission rate, complications, recurrence risk, and predictive factors for surgical success.

Study Design and Methodology

This prospective single-center study analyzed 230 consecutive adult patients (over 18 years old) who underwent EETS for Cushing’s disease between 2008 and 2013 by a single neurosurgeon. All patients had confirmed clinical and biological signs of Cushing’s disease, with or without pituitary tumor detection on dedicated MRI.

🔹 Remission Criteria: Biochemical remission was defined as a postoperative serum cortisol level <5 μg/dl on the second day after surgery, requiring glucocorticoid replacement therapy.

Key Findings

📌 Overall remission rate: 79.1% (182/230 patients).

📌 Patients with positive MRI: 82.5% remission rate (132/160).

📌 Patients with negative MRI: 71.4% remission rate (50/70).

📌 No significant statistical difference between the two groups (p = 0.077).

Complications and Recurrence

💡 Postoperative complications occurred in 77 patients, but no deaths were reported.

💡 Diabetes insipidus was observed in 22% (transient) and 6.4% (long-term) of cases.

💡 No cerebrospinal fluid (CSF) leakage was recorded postoperatively.

💡 Recurrence rate: 9.8%, with a mean recurrence time of 32.7 ± 15.2 months.

Predictive Factors for Remission

🔹 The presence of pituitary microadenoma on MRI was associated with higher remission rates.

🔹 A positive MRI (showing a visible adenoma) was a favorable factor for surgical success.

Conclusion

Endoscopic endonasal transsphenoidal surgery is an effective and safe treatment option for Cushing’s disease, achieving high remission rates even in patients with negative MRI findings. Early detection of microadenomas and careful patient selection can improve surgical outcomes.