The surgical and local ablation strategy for the treatment of resectable synchronous and
metachronous colorectal liver metastases(CRLM) has not still been defined. The purpose of
this study is to compare two treatment strategies in which simultaneous resection of both
primary and secondary tumor of synchronous CRLM(SCRLM) and resection of metachronous
CRLM(MCRLM) is compared with resection of primary tumor and ablation of secondary tumor in
SCRLM and ablation of MCRLM. Endpoints include the rate of severe complications and survival.