Trends and outcomes of simultaneous versus staged resection of synchronous colorectal cancer and colorectal liver metastases

Abstract Background The objective of this study was to assess trends in the use as well as the outcomes of patients undergoing simultaneous versus staged resection for synchronous colorectal liver metastases. Methods Patients undergoing resection for colorectal liver metastases between 2008 and 2018 were identified using a multi-institutional database. Trends in use and outcomes of simultaneous resection of colorectal liver metastases were examined over time and compared with that of staged resection after propensity score matching. Results Among 1,116 patients undergoing resection for colorectal liver metastases, 690 (61.8%) patients had synchronous disease. Among them, 314 (45.5%) patients underwent simultaneous resection, while 376 (54.5%) had staged resection. The proportion of patients undergoing simultaneous resection for synchronous colorectal liver metastases increased over time (2008: 37.2% vs 2018: 47.4%; ptrend = 0.02). After propensity score matching (n = 201 per group), patients undergoing simultaneous resection for synchronous colorectal liver metastases had a higher incidence of overall (44.8% vs 34.3%; P = .03) and severe complications (Clavien-Dindo ≥III) (16.9% vs 7.0%; P = .002) yet comparable 90-day mortality (3.5% vs 1.0%; P = .09) compared with patients undergoing staged resection. The incidence of severe morbidity decreased over time (2008: 50% vs 2018: 11.1%; ptrend = 0.02). Survival was comparable among patients undergoing simultaneous versus staged resection of colorectal liver metastases (3-year overall survival: 66.1% vs 62.3%; P = .67). Following simultaneous resection, severe morbidity and mortality increased incrementally based on the extent of liver resection and complexity of colectomy. Conclusion While simultaneous resection was associated with increased morbidity, the incidence of severe morbidity decreased over time. Long-term survival was comparable after simultaneous resection versus staged resection of colorectal liver metastases.