大肠癌(Colorectal cancer,CRC)是西方国家最常见的实体瘤,占恶性肿瘤死亡率的10%。近年来,我国发病率也呈上升趋势。肝脏是大肠癌最常见的远位转移器官,初诊时约10%~25%已有同时性肝转移,此后20%~25%的患者发生异时性肝转移[1]。国内同时性肝转移为5.2%~6.0%。肝转移是大 Colorectal cancer (CRC) is the most common solid tumor in western countries, accounting for 10% of the mortality of malignant tumors. In recent years, the incidence of our country has also been on the rise. Liver is the most common distant metastasis of colorectal cancer, with about 10% -25% of patients having simultaneous liver metastases at the time of first visit, and heterotopic liver metastases occurring in 20% -25% of patients afterwards. Domestic simultaneous liver metastasis was 5.2% ~ 6.0%. Liver metastasis is large