In patients undergoing parenchyma-sparing liver resection for colorectal metastases, laparoscopic surgery was associated with significantly less postoperative complications compared to open surgery. Laparoscopic resection was cost-effective compared to open resection with a 67% probability. The rate of free resection margins was the same in both groups. Our results support the continued implementation of laparoscopic liver resection.

Modifying the t-CS by replacing disease-free interval, number of metastases, and CEA level with RAS mutation status produced an m-CS that outperformed the t-CS. The m-CS is therefore a simple validated tool that predicts survival after resection of CLM.

My special appreciation goes to a talented surgeon, my colleague and friend Dr. Åsmund Fretland, who has been a remarkable co-supervisor to me. Your research and surgical skills, positiveness and the ability to solve problems quickly have always impressed me. Thank you for letting me to take over your work in the OSLO-COMET trial and for introducing me to all the details. It is always my great pleasure to draft articles together with you, be your assistant at liver surgery and attend conferences together with you. My classmate, colleague and friend Dr. Mushegh Sahakyan deserves my deepest gratitude. You are a role model for me as a young talented and hard-working researcher. I have learned a lot from our discussions about surgical procedures, article drafting, methodologies and statistics in research. I am very glad that you are back to Norway and our research group. I look forward to continuing our fruitful cooperation and Armenian barbeques together. I would like to thank Prof. Erik Fosse for the opportunity to work at the Intervention Centre, where you have created an outstanding multi-speciality research team. Communication with multidisciplinary research teams and professionals at IVS have extended my horizons. It was my pleasure to work alongside Marianne Berg, Linda Engvik, nurses and radiology team.

Objective: We conducted a randomized, controlled, noninferiority trial to investigate if intravenous, multimodal, patient-controlled analgesia (IV-PCA) could be noninferior to multimodal thoracic epidural analgesia (TEA) in patients undergoing open liver surgery. Summary Background Data: The increasing use of minimally invasive techniques and fast track protocols have questioned the position of epidural analgesia as the optimal method of pain management after abdominal surgery. Methods: Patients operated with open liver resection between February 2012 and February 2016 were randomly assigned to receive either IV-PCA enhanced with ketorolac/diclofenac (IV-PCA, n = 66) or TEA (n = 77) within an enhanced recovery after surgery protocol. Noninferiority would be declared if the mean pain score on the numeric rating scale (NRS) for postoperative days (PODs) 0 to 5 in the IV-PCA group was no worse than the mean pain score in the TEA group by a margin of <1 point on an 11-point scale (0–10). Results: The primary endpoint, mean NRS pain score was 1.7 in the IV-PCA group and 1.6 in the TEA group, establishing noninferiority. Pain scores were lower in the TEA group on PODs 0 and 1, but higher or equal on PODs 2 and 5. Postoperative hospital stay was significantly shorter for patients in the IV-PCA group (74 vs 104 h, P < 0.001). The total opioid consumption during the first 3 days was significantly lower in the IV-PCA group. Conclusions: IV-PCA was noninferior to TEA for the treatment of postoperative pain in patients undergoing open liver resection.