Clinical Outcomes After Endoscopic Endonasal Resection of Giant Pituitary Adenomas

Giant pituitary adenomas represent a surgical challenge. We present the results of the endoscopic endonasal approach (EEA) for giant pituitary adenomas.

We retrospectively reviewed the medical records of 55 patients with giant pituitary adenomas (>4 cm in maximum diameter) who underwent surgery with an EEA between 2008 and 2016. Factors affecting the extent of resection were evaluated.

The mean patient age was 55.5 years. Tumors were nonfunctional in all but 4 patients, including 2 with growth hormone-secreting tumors, 1 with an adrenocorticotropic hormone-secreting tumor, and 1 with prolactinoma. Gross total resection was achieved in 24 patients (44%), and near-total resection (>90%) was achieved in 26 patients (47%). A multilobular configuration (P = 0.002) and cavernous sinus invasion (P = 0.044) negatively affected the extent of resection, whereas tumor size, intraventricular, and anterior or posterior fossa extension did not. Ten patients underwent adjuvant radiotherapy. All patients with hormone-secreting adenomas required adjuvant medical and/or radiotherapy to achieve biochemical remission. Postoperative vision was improved or normalized in 32 patients (66%), stable in 15 patients (31%), and worsened in 1 patient. A new hormonal deficit occurred in 8 patients (17%), whereas recovery of an existing hormonal deficit occurred in 6 patients (20%). The mean duration of follow-up was 41 months. Tumor recurrence/progression occurred in 6 patients (11%). Complications included apoplexy of residual tumor resulting in ischemic stroke in 1 patient, postoperative cerebrospinal fluid leak in 1 patient, and permanent diabetes insipidus in 4 patients (7%).

Surgery with the EEA is an excellent option for managing giant pituitary adenomas. It results in superior clinical outcomes to those obtained using traditional microscopic transsphenoidal and transcranial approaches as reported in the literature.