Management of Colorectal Cancer with Synchronous Liver Metastases: An Inception Cohort Study (CoSMIC)

Background: Approximately one-fifth of patients with colorectal cancer present with hepatic metastases. There are limited prospective data on the outcomes of synchronous combined liver and bowel surgery and liver-first or bowel-first routes where contemporary chemo(radio)therapy is integrated into management. Methods: Between 1 April 2014 and 31 March 2017, 125 patients with colorectal cancer and synchronous liver metastases were recruited. Data are reported on pathway-specific outcomes, including perioperative complications, treatment completion, and overall and disease-free survival. The study was registered with ClinicalTrials.gov (NCT02456285). Results: There was no difference in age, body mass index, or Charlson score between surgical groups. Neoadjuvant chemotherapy was used in 50 (40%) patients for a mean duration of 4.6 months (standard deviation [SD] 5.4), and mean time from completion of chemotherapy to surgery was 2.6 months (SD 1.9). Complications were similar between patients completing the synchronous and staged pathways (p = 0.66). Mean total inpatient stay was 16.5 days (SD 8.1) for staged surgery compared with 16.8 days (SD 10.3) for the synchronous group (t-test; p = 0.91). There was no difference in time to treatment completion between pathways. Thirty six (35%) patients were disease-free at 12 months, with no significant difference between groups (Chi-square, p = 0.448). Quality of life was similar in all surgical groups. Conclusions: Perioperative complications and oncological and healthcare occupancy outcomes are equivalent between patients completing staged and synchronous pathways for the management of patients with colorectal cancer and synchronous liver metastases. Future studies should focus on optimizing the criteria for pathway selection, incorporation of cancer genomics data, and patient (user) preferences.