Long-term outcome of liver resection for colorectal metastases in the presence of extrahepatic disease: A multi-institutional Japanese study

Background/Purpose The purpose of the present study was to assess long-term outcomes following liver resection for colorectal liver metastases (CRLM) with concurrent extrahepatic disease and to identify the preoperative prognostic factors for selection of operative candidates. Methods In this retrospective, multi-institutional study, 3820 patients diagnosed with CRLM during 2005-2007 were identified using nationwide survey data. Data of identified patients with concurrent extrahepatic lesions were analyzed to estimate the impact of liver resection on overall survival (OS) and to identify preoperative, prognostic indicators. Results Three- and 5-year OS rates after liver resection in 251 CRLM patients with extrahepatic disease (lung, n = 116; lymph node, n = 51; peritoneal, n = 37; multiple sites, n = 23) were 50.2% and 32.0%, respectively. Multivariate analysis revealed that a primary tumor in the right colon, lymph node metastasis from the primary tumor, serum carbohydrate antigen (CA) 19-9 level >37 UI/mL, the site of extrahepatic disease, and residual liver tumor after hepatectomy were associated with higher mortality. We proposed a preoperative risk scoring system based on these factors that adequately discriminated 5-year OS after liver resection in training and validation datasets. Conclusions Performing R0 liver resection for colorectal liver metastases with treatable extrahepatic disease may prolong survival. Our proposed scoring system may help select appropriate candidates for liver resection.