Comparing redo surgery and stereotactic radiosurgery for recurrent, residual, and/or tumors showing progression in nonfunctioning pituitary adenomas: A systematic review and meta-analysis

Background: Non-functioning pituitary adenomas (NFPAs) are well-differentiated benign tumors originating from the adenohypophyseal cells of the pituitary gland. They present with headaches, visual disorders, or cranial nerve deficits. NFPAs can recur, progress, or present as residual tumors. We, therefore, conducted this review to compare the effects of both revision surgery and stereotactic surgery on tumor size, visual status, endocrine status, and complications. Methods: A systematic review of published literature on recurrent, residual, or progressing NFPAs that underwent redo surgery or stereotactic radiosurgery from the inception till June 2020 was conducted as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Thirteen records (1209 patients) were included, and risk ratio (RR) and 95% confidence intervals (CIs) estimated from each study were pooled using a random-effects meta-analysis model. Results: Redo surgery was the preferred intervention in patients presenting with larger tumor sizes and was more effective in reducing the tumor size as compared to stereotactic radiosurgery (SRS) (risk ratio [RR] 56.14; 95% CI, 16.45–191.58). There was more visual loss with revision surgery as compared to SRS (risk ratio [RR] 0.08; 95% CI, 0.03–0.20). However, SRS was associated with fewer complications, such as new diabetes insipidus, as compared to the redo surgery (risk ratio [RR] 0.01; 95% CI 0.01–0.03). Conclusion: Redo surgery is the superior choice in the treatment of recurrent/residual or progressing NFPAs if the tumor size is large and an immediate reduction in tumor burden through debulking is warranted. However, redo surgery is associated with a higher risk of visual loss, new endocrinopathies, and other complications, in contrast to SRS.