LAUSR

734Background: It is still a topic of ongoing debate as to which of the two agents, anti-VEGF antibody or anti-EGFR antibody, is more effective in patients with KRAS Exon 2 or RAS wild-type metastatic colorectal cancer (mCRC) in the first-line setting. ATOM is a multicenter, randomized trial comparing mFOLFOX6 plus bevacizumab (Bmab arm) with mFOLFOX6 plus cetuximab (Cmab arm) in patients with liver-limited metastases unsuitable for upfront resection. Methods: Patients with previously untreated mCRC were eligible if they had ≥5 liver-limited metastatic lesions and/or had liver-limited metastases with the maximum lesion diameter of > 5cm. Patients with KRAS Exon2-wild were registered but after Jan 2015 limited to those with all RAS-wild. Primary endpoint was progression-free survival (PFS), which was defined as the time from randomization to disease progression, recurrence after resection by surgery, or death from any cause (Central review). Key secondary endpoints included overall response rate (ORR), liv...