Starting point for benchmarking outcomes and reporting of pituitary adenoma surgery within the European Reference Network on Rare Endocrine Conditions (Endo-ERN): results from a meta-analysis and survey study

Objective: The European Reference Network on Rare Endocrine Conditions (Endo-ERN) aims to organize high-quality healthcare throughout Europe, inc luding care for pituitary adenoma patients. As surgery is the mainstay of treatment, we aimed to describe the current surgical practice and published surgical outcomes of pi tuitary adenoma within Endo-ERN. Design and Methods: Systematic review and meta-analysis of studies reporting surgical outcomes of pituitary adenoma patients within Endo-ERN MTG6 pituitary reference centers between 2010 and 2019. A survey was completed by refere nce centers on their current surgical practice. Results: A total of 18 out of 43 (42%) reference centers located in 7 of the 20 (35%) MTG6- represented countries published 48 articles. Remission rates we re 50% (95% CI: 42–59) for patients with acromegaly, 68% (95% CI: 60–75) for Cushing’s disease, and 53% (95% CI: 39–66%) for prolactinoma. Gross total resection was achieved in 49% (95% CI: 37–61%) of patients and visual improvement in 78% (95% CI: 68–87). Mort ality, hemorrhage, and carotid injury occurred in less than 1% of patients. New-onset hypopituitarism occurred in 16% (95% CI: 11–23), transient diabetes insipidus in 12% (95 % CI: 6–21), permanent diabetes insipidus in 4% (95% CI: 3–6), syndrome of inappropria te secretion of antidiuretic hormone (SIADH) in 9% (95% CI: 5–14), severe epist axis in 2% (95% CI: 0–4), and cerebrospinal fluid leak in 4% (95% CI: 2–6). Thirty-five (81 %) centers completed the survey: 54% were operated endoscopically and 57% were together with an ENT surgeon. Conclusion: The results of this study could be used as a first benchmark for the outcomes of pituitary adenoma surgery within Endo-ERN. However, the hete rogeneity between studies in the reporting of outcomes hampers comparability and warrants outcome collection through registries.