Outcome Squares integrating efficacy and safety, as applied to functioning pituitary adenoma surgery.

Purpose Transsphenoidal surgery is standard care in the treatment of hormone-secreting pituitary adenomas. Current clinician-reported surgical outcome measures are one-dimensional, typically focussing primarily on complete or partial resection and secondarily on complication rates. However, outcomes are best reflected by the delicate balance of efficacy and complications at patient level. This study proposes a novel way to classify and report outcomes, integrating efficacy and safety at the patient level. Methods Retrospective chart review of all pure endoscopic transsphenoidal surgical procedures for acromegaly, Cushing's disease, and prolactinoma between 2010-2018 in a single tertiary referral centre. We present our results in a classic (remission and complications separate) and in a novel Outcome Square integrating both outcomes, focusing on intended and adverse effects (long-term complications). This resulted in four outcome groups, ranging from good to poor. We use this approach to present these outcomes for several subgroups. Results 198 surgical procedures were included (44 reoperations). Remission was achieved in 127 operations (64%). Good outcome was observed after 121 (61%), and poor outcome after 6 (3%) operations. When intended effect of surgery was applied (instead of remission), good outcome as intended was achieved after 148 of 198 surgeries (75%) and poor outcome after 4 (2%). Conclusion Quality of a surgical intervention can be presented in 4 simple categories, integrating both efficacy and safety with flexibility to adapt to the individualized situation at patient, disease, and surgical strategy and to the outcome of interest.