Endocrinological outcomes following endoscopic and microscopic transsphenoidal surgery in 113 patients with acromegaly.

BACKGROUND

To describe outcomes and complications in patients undergoing transsphenoidal surgery for acromegaly using the 2010 consensus criteria for biochemical remission.

METHODS

Retrospective review of 113 treatment naïve patients who underwent transsphenoidal surgery with the endoscopic (n=66) and the endonasal microscopic technique (n=47). Cure was defined if the age and sex-adjusted IGF-1 level was normal and either the basal GH was <1 ng/ml or the nadir GH was <0.4 ng/ml following oral glucose suppression at last follow-up.

RESULTS

The mean age at presentation was 38.1 ± 7.1 years and 86% of tumors were macroadenomas. Adenoma sizes averaged 21.1 ± 9.7 mm, but 56% of all tumors were ≥ 2 cm in size and 43.4% were invasive. Remission rates between endoscopic and microscopic transsphenoidal surgery did not differ significantly overall (28.8% versus 36.2%). On univariate analysis, a preoperative GH level <40 ng/ml, adenoma size <20mm and non-invasiveness were predictors of remission at follow-up. Although there were no statistically significant differences in remission rates between the endoscopic and microsurgical groups, surgically induced hypopituitarism was less frequent with the former.

CONCLUSIONS

We report our surgical experience with predominantly large, invasive GH adenomas using the 2010 criteria for cure. Patients with smaller, non-invasive tumors with lower preoperative GH levels are most likely to achieve remission. Outcomes with either the microscopic or endoscopic approach do not differ significantly, although the rate of surgically induced hypopituitarism may be higher with the former. Transsphenoidal surgery remains the first line of treatment for patients with acromegaly, but invasive adenomas will frequently require adjuvant therapy.