Defining a textbook outcome for the resection of colorectal liver metastases.

Introduction: Textbook outcomes (TBO) are composite measures of care which may be superior in assessing quality compared to traditional methods. We aim to define TBO which are specific to surgical resection of colorectal liver metastases, and investigate their impact on survival.

Methods: Single center analysis of all liver resections performed at our center from 2009 to 2020. A Cox model was used to identify perioperative outcomes which impacted on overall survival. These were retained with important postoperative outcomes to form a "TBO." The impact of a TBO on overall survival was investigated using Kaplan-Meier curve analysis.

Results: TBO was achieved in 72.2% (197/273) of resections. Major morbidity (Clavien-Dindo ≥3) at 19.4% was the major limiting factor in not achieving a TBO. TBO was associated with improved 3-year (77% vs. 55%), 5-year (60.7% vs. 42.5%), and median (93 vs. 44 months) overall survival (log-rank test, p = 0.006). Multivariable analysis revealed age >65 years, American Society of Anaesthesiologists Grade III-IV, and resection of >2 segments as factors predictive of not achieving a TBO.

Conclusion: TBO is a useful composite measure in surgery for colorectal liver metastases. It can highlight areas which may be targeted for quality improvement and be useful as a tool to examine variation between centers. Achieving a TBO is associated with a significant improvement in survival.