Outcomes of endoscopic and microscopic transsphenoidal surgery on non-functioning pituitary adenomas: a systematic review and meta-analysis

Both microscopic and endoscopic transsphenoidal surgery are effective approaches for nonfunctioning pituitary adenomas. The issue on the comparison of their efficacy and safety remains inconsistent. A thorough search of the literatures (PubMed, EMBASE, MEDLINE) were performed up to March 2017. Studies reporting outcomes of microscopic or endoscopic transsphenoidal surgery on nonfunctioning pituitary adenomas were included. A meta-analysis was performed focusing on the early stage and long term outcomes. The final search yielded 19 eligible studies enrolling 3847 patients, 389 of them underwent microscopic approach and 3458 of them with endoscopic approach. As to the early stage outcomes, the rate of gross tumor resection was significantly higher in the endoscopic group than that in microscopic group (73% versus 60%, P < 0.001). Meanwhile, endoscopic approach showed priority over microscopy on postoperative hypopituitarism (63% versus 65%, P < 0.001) and CSF leakage (3% versus 7%, P < 0.001). For the long term outcomes, the rate of visual improvement was significant higher in the endoscopic group than that in microscopic group (77% versus 50%, P < 0.001). However, there was no significant difference between the groups regarding the rate of permanent diabetic insipidus and meningitis. The endoscopic approach may be associated with higher rate of gross tumor movement and lower risk of postoperatively complications for treating nonfunctioning pituitary adenoma, when compared with microscopic approach. However, the confidence was shorted due to limited high quality evidence (largely randomized and controlled studies).