Extent of Resection, Visual, and Endocrinologic Outcomes for Endoscopic Endonasal Surgery for Recurrent Pituitary...

To assess outcomes after endoscopic endonasal surgery for recurrent or residual pituitary adenomas.

We retrospectively analyzed 61 patients from 2009 to 2016 who underwent endoscopic endonasal surgery for recurrent or residual pituitary adenomas after previous microscopic or endoscopic transsphenoidal operation.

The previous surgical approach was endoscopic endonasal in 55.7% and microscopic in 44.2% of patients. The mean preoperative maximal tumor diameter was 2.3 cm. Tumor commonly invaded the suprasellar cistern (63.9%). Gross total resection (GTR) was achieved in 31 patients (51.7%). GTR rate was 68.4% and 21.7% for Knosp grade 0-2 and grade 3-4 tumors, respectively (P < 0.001). GTR was 73.1% and 35.3% for patients with previous microscopic and endoscopic transsphenoidal surgery, respectively (P = 0.002). On multivariate analysis, smaller tumor size (odds ratio [OR], 1.1 per cm; P = 0.007), Knosp grade 0-2 (OR, 9.7; P = 0.002), and previous microscopic approach (OR, 12.7; P = 0.007) were independent predictors of GTR. Preoperative visual deficit outcome was improved in 32.5%, unchanged in 62.5%, and worse in 5.0%. New postoperative endocrinopathies included adrenal insufficiency (6.5%), hypothyroidism (8.1%), hypogonadism (6.5%), and diabetes insipidus (4.9%). Complications included postoperative cerebrospinal fluid leak (4.9%), meningitis (1.6%), medical complications (4.9%), and postoperative hematoma requiring re-exploration (3.2%).

The endoscopic endonasal approach provides a safe and effective option for recurrent pituitary adenomas. Smaller tumor size, absence of cavernous sinus invasion, and previous microscopic approach were independent predictors of GTR. This finding might suggest that inadequate exposure or limited viewing angle may adversely affect extent of resection in primary microscopic surgeries.