Simultaneous resections of colorectal cancer and synchronous liver metastases: factors associated with textbook outcome and major complications

Introduction Simultaneous resection of colorectal cancer and synchronous liver metastases is widely adopted but less is known of the safety of simultaneous major hepatectomies and rectal resections. This study aimed to identify factors associated with textbook outcome in liver surgery (TOLS) and major complications following simultaneous resections. Method Patients undergoing simultaneous liver and colorectal resections at Karolinska University Hospital (2013–2023) were retrospectively reviewed. Logistic regression analysed factors influencing major complications, defined as Clavien-Dindo ≥ 3b, and TOLS. Survival was assessed using Kaplan-Meier and log-rank test. Result Among 193 patients, 142 underwent colon (17 cytoreductive surgery ± HIPEC) and liver resections (22 major resections). 51 underwent rectal (8 cytoreductive surgery ± HIPEC) and liver resections (one hemihepatectomy). TOLS was achieved in 84 (44%) patients. Factors associated with TOLS were lower ASA score (OR 2.4, 95% CI: 1.2-4.7) and minimally invasive surgery (MIS) (OR 3.7, 95% CI 1.3-10.3). Major complications occurred in 28 (15%) patients. Age and ASA score were associated with major complications, but surgical (MIS vs open, major vs minor liver resections, colon vs rectum resections, the addition of cytoreductive surgery ± HIPEC) and tumour factors (tumour and nodal stage, metastasis number, size and segmental distribution) were not. Major complications impaired 5-year survival (55% vs 29%, p=0.013), whereas achieving TOLS did not. Discussion Simultaneous resections, including major hepatectomies and rectal resections, are safe with proper patient selection. Although major morbidity was not impacted by specific surgical or tumour variables, it significantly impaired long-term survival and should be minimized.