Outcomes of surgical treatment for nonfunctioning pituitary adenomas: a systematic review and meta-analysis

P>Background Surgery is commonly used in the management of pituitary nonfunctioning adenomas (NFPA). The goal of this systematic review and meta-analysis is to evaluate the effect of surgery on mortality, surgical complications, pituitary function and vision. Methods We searched MEDLINE, EMBASE and Cochrane CENTRAL, queried experts and reviewed the reference list of included publications. Eligible studies were comparative and noncomparative longitudinal studies that enroled patients with NFPA who underwent surgery (alone or in combination with other therapies). Reviewers, working independently and in duplicate, determined study eligibility with adequate reproducibility and extracted descriptive, quality and outcome data. Risks, relative risks (RR) and 95% confidence intervals (CIs) were estimated from each study and pooled using random-effects meta-analysis. Results Most included studies were uncontrolled case series in which patients received a combination of surgery and radiotherapy. The overall quality of the evidence was very low. Median follow-up was 4 center dot 29 years. When surgery was not combined with radiotherapy, there was an increased risk of tumour recurrence (RR 1 center dot 97; 95% CI, 1 center dot 15-3 center dot 35). Complications were more likely with the transcranial than with the transsphenoidal approach (mortality RR 4 center dot 89; 95% CI, 3 center dot 15-6 center dot 47; new anterior pituitary deficits RR 4 center dot 90; 95% CI, 2 center dot 94-7 center dot 82; and persistent diabetes insipidus RR 2 center dot 50; 95% CI, 1 center dot 05-5 center dot 35). Overall, transsphenoidal surgery had fairly low perioperative mortality (< 1%) and low complication rate (< 5% for all patient-important outcomes), but only less than a third of the patients had improvement in pituitary function. Conclusions Observational evidence supports the association between a combined approach of transsphenoidal surgery with radiotherapy and improvements in visual field defects and reduction in tumour recurrence.