Endoscopic Endonasal Treatment of Pituitary Adenomas Invading the Cavernous Sinus: Surgical Outcome in 374 Patients

Introduction: The advent of endoscopic endonasal technique has given a new horizon to cavernous sinus (CS) surgery. Indeed, the preliminary results reported by multiple authors along the last decade have revealed to be encouraging, showing a satisfactory tumor removal rate, endocrinological remission, and low morbidity. After 15 years of experience, we reviewed our surgical series of CS invading pituitary adenomas (PTA) to analyze the outcome of this approach in a larger surgical series with a more relevant follow-up.

Patients and Methods: All consecutive patients with PTA involving the CS operated in our center from 1998 to 2013 were collected. All patients underwent preoperative baseline biohumoral assessments, visual field and acuity measurements, neurological examinations, and MRI. These examinations were repeated 3 months after surgery and then every 6 or 12 months to assess the neuroradiological and clinical outcome. During surgery, the effective intraoperative CS invasion (ICSI) was evaluated. At last follow-up, the surgical and endocrinological results were analyzed to assess the comprehensive evaluation as remission, control or no control of the tumor. Statistical analysis was performed to analyze the association between the CS invasion and comprehensive evaluation.

Results: The series includes 374 patients (32% of at the entire series of PTA), underwent 393 surgical procedures, consisting in 314 midline transsphenoidal approach and 75 ethmoid-pterygo-sphenoidal approaches. The former was performed for PTA invading the medial and/or the superoinferior compartments of CS, while the latter was indicated for cases invading the anteroinferior and/or lateral compartment. Radical tumor removal was obtained in 248 cases (66.3%). Surgery permitted to achieve a complete endocrinological and tumor remission in 231 (61.8%) patients and allowed to obtain its control by other therapies in 128 cases (34.8%). Morbidity rate was of 6.6%, and the vast majority of complications resulted without any permanent sequelae. Permanent CN palsy was observed in only two cases (0.4%). At statistical analysis, the primary surgery, the lower Knosp, and ICSI scores confirmed to be associated with a more radical tumor removal (p = 0.007 and p = 0.001) and better comprehensive evaluation (p = 0.005 and p = 0.001).