Systematic review of outcomes of patients undergoing resection for colorectal liver metastases in the setting of extra hepatic disease

Background Surgical resection for patients with colorectal liver metastases (CRLM) can offer patients a significant survival benefit. We hypothesised that patients with CRLM and extra hepatic disease (EHD) undergoing metastasectomy had comparable survival and describe outcomes based on the distribution of metastatic disease. Methods A systematic search using a predefined registered protocol was undertaken between January 2003 and June 2012. Primary exposure was hepatic resection for CRLM and primary outcome measure was overall survival. Meta-regression techniques were used to analyse differences between patients with and without extra hepatic disease. Findings From a pool of 4996 articles, 50 were retained for data extraction (3481 CRLM patients with EHD). The median survival (MS) was 30.5 (range, 9-98) months which was achieved with an operative mortality rate of 0-4.2%. The 3-year and 5-year overall survival (OS) were 42.4% (range, 20.6-77%) and 28% (range, 0-61%) respectively. Patients with EHD of the lungs had a MS of 45 (range, 39-98) months versus lymph nodes (portal and para-aortic) 26 (range, 21-48) months versus peritoneum 29 (range, 18-32) months. The MS also varied by the amount of liver disease - 42.2 months (<two lesions) versus 39.6 months (two lesions) versus 28 months (≥three lesions). Interpretation In the evolving landscape of multimodality therapy, selective hepatic resection for CRLM patients with EHD is feasible with potential impact on survival. Patients with minimal liver disease and EHD in the lung achieve the best outcome.