Oncological outcomes of major liver resection following portal vein embolization: a systematic review and a meta-analysis

Abstract

Background Preoperative portal vein occlusion with either percutaneous portal vein embolization (PVE) or portal vein ligation (PVL) is routinely used to induce liver hypertrophy prior to major liver resection in patients with hepatic malignancy. While this increases the future liver remnant (FLR) and hence the number of patients suitable for resection, recent evidence suggests that induction of liver hypertrophy pre-operatively may promote tumour growth and increase recurrence rates. Aim of the current study is to evaluate the impact of PVE on hepatic recurrence rate and survival in patients with colorectal liver metastases (CRLM). Methods Medline, Embase and Web of Science databases were searched to identify studies assessing the oncological outcomes of patients undergoing major liver resection for CRLM following PVE. Studies comparing patients undergoing one stage liver resection with or without pre-operative PVE were included. The primary outcome was hepatic recurrence (HR). Secondary outcomes were 3- and 5-year overall survival (OS). Results Of the 2131 studies identified, six nonrandomized studies (n=668) met the eligibility criteria comparing outcomes of patients undergoing major liver resection with or without PVE (n=182 vs. n=486 respectively). The median follow-up time ranged from 23.5 to 46 months. There was no significant difference in HR (OR, 0.78; 95% CI, 0.42 to 1.44, p=0.41), 3-year OS (OR, 0.80; 95% CI, 0.56 to 1.14, p=0.22) or 5-year OS (OR, 1.12; 95% CI, 0.40 to 3.11, p=0.82). Conclusion PVE in patients with CRLM has no adverse effect on hepatic recurrence or overall survival following major liver resection.