Survival Outcomes After Portal Vein Embolization and Liver Resection Compared With Liver Transplant for Patients With Extensive Colorectal Cancer Liver Metastases.

Importance: Portal vein embolization (PVE) has been implemented in patients with extensive colorectal liver metastases to increase the number of patients able to undergo liver resection. Liver transplant could be an alternative in selected patients with extensive liver-only disease, and we have recently shown promising survival outcomes. Objective: To compare overall survival (OS) among patients with colorectal cancer and high liver metastasis tumor load who were treated with liver transplant or with PVE and liver resection. Design, Setting, and Participants: This comparative effectiveness research study assessed 50 patients with colorectal cancer liver metastases who were previously enrolled in liver transplant studies between November 2006 and August 2019 at Oslo University Hospital in Norway. Those patients were compared with a retrospective cohort of 53 patients in the Oslo University Hospital PVE database from March 2006 through November 2015 with similar selection criteria who underwent PVE and liver resection. Main Outcomes and Measures: The OS among patients with high tumor load after liver transplant was compared with that among patients with high tumor load who underwent PVE and liver resection. High tumor load was defined as 9 or more metastatic tumors or a diameter of 5.5 cm or longer for the largest liver lesion. Results: In the PVE cohort of 53 patients, the median age was 61.8 years (range, 34.3-71.3 years), and 36 patients (68%) were men. The 5-year OS rate among 38 patients who underwent liver resection after PVE was 44.6%. The 5-year OS rate for patients with high tumor load was 33.4% for those who underwent liver transplant and 6.7% for those who underwent PVE. Among patients with high tumor load and left-sided primary tumors, the 5-year OS rate was 45.3% for those receiving a liver allograft and 12.5% for those treated with PVE and liver resection. Conclusions and Relevance: Patients with nonresectable disease, an extensive liver tumor load, and left-sided primary tumors had long OS after liver transplant, exceeding the survival outcome for those patients treated with PVE and liver resection.