Authors: Andrew Scott Little, MD, FAANS; TRANSSPHER Study Group (Phoenix, AZ)


Many surgeons have adopted fully endoscopic over microscopic transsphenoidal surgery for pituitary tumors, although no high-quality evidence demonstrates superior patient outcomes with endoscopic surgery. Previously, we presented an analysis of extent of tumor resection from a multicenter prospective study, which demonstrated that these techniques yielded similar gross total tumor resection rates. In this abstract, we present the comparative pituitary gland endocrine outcomes.


Adrenal, thyroid, gonadal, and posterior gland function were evaluated before and 6 months after surgery using standard endocrine laboratory testing. Results were centrally adjudicated.


Seven pituitary centers and 15 surgeons participated. 260 patients were enrolled (82 with microscopic procedures, 177 with endoscopic procedures, 1 cancelled surgery).  Baseline patient tumor characteristics were similar between groups. A new deficiency of at least one hormone axis was noted in 19 of 67 patients (28.4%) in the microscopic cohort and 14 of 145 patients (9.7%) in the endoscopic cohort (P<0.001; OR, 3.7; 95% CI, 1.7-7.7). Improvement in at least one hormone axis was noted in 12 of 50 patients (24.0%) in the microscopic group and 20 of 93 patients (21.5%) in the endoscopic group (P=0.83; OR, 1.2; 95% CI, 0.5-2.7).


Increased rates of new adrenal insufficiency (11 of 59 patients [18.6%] vs. 4 of 135 patients [3.0%]; P<0.001; OR, 7.5; 95% CI, 2.5-22.1) and diabetes insipidus (7 of 79 patients [8.9%] vs. 4 of 166 patients [2.4%]; P=0.04; OR, 3.9; 95% CI, 1.2-12.2) were observed in the microscopic cohort compared with the endoscopic cohort. Rates of individual hormone axis recovery were similar between groups (P>0.30) for all evaluated pituitary hormone axes. Individual surgeon effects will be presented.


The endoscopic technique was associated with lower rates of new postoperative adrenal insufficiency and diabetes insipidus. We hypothesize that the superior view provided by the endoscopic technique facilitates gland preservation.