516 Background: Hepatic metastasectomy is the only curative option for patients (pts) with colorectal liver metastases (CRLM) but the optimal sequence of surgery and chemotherapy has not been established. We evaluated disease-free survival (DFS) in pts who were treated with difference sequences for resectable CRLM. Methods: Pts who had radiologically diagnosed with CRLM and underwent preoperative chemotherapy (preopCT) followed by surgery or upfront hepatic resection from Jan 2008 to Dec 2010, in National Cancer Center, Korea, were identified and their medical records were reviewed. Pts with number of metastatic nodules (mets) less than 6, and who were untreated for metastastic setting were analyzed. Those with tumor invasion of major intrahepatic vessels, extrahepatic metastases, or combined other advanced cancer were excluded. Results: Of 208 pts who underwent hepatic metastasectomy for suspicious CRLM, 123 pts who fulfilled the above criteria were analyzed. 34 (28%) pts received preopCT followed by surgery and 89 (72%) pts underwent upfront surgery. Postoperative chemotherapy was administered for 34 (100%) of preopCT group and 73 (82%) of upfront surgery group. Number of mets, baseline tumor marker levels, and R0 resection rate were similar between the two groups. But, early relapse was more in upfront surgery group. DFS at 3 year was 14% (95% CI 29%-34%) in preopCT group and 48% (95% CI 36%-59%) in upfront surgery group. In multivariate analysis, age > 65, Charlson comorbidity index > 0, mets≥3, and R1/R2 resection were significantly associated with increased risk for DFS events, while PreopCT was marginally associated with adverse outcome (Table). Conclusions: Upfront surgery, rather than preoperative chemotherapy followed by surgery, might be a favorable treatment option for resectable CRLM in terms of DFS. [Table: see text]