Abstract: Advances in resection margin of colorectal liver metastases        SONG Hua-chuan, WANG Ji-zhou.Department of Hepatobiliary Surgery, the First Affiliated Hospital of University of Science and Technology of China, Hefei 230001,China
Corresponding author: WANG Ji-zhou, E-mail：wangjoe@ustc.edu.cn  
Abstract    Surgical treatment is the most effective treatment for colorectal liver metastases (CRLM), and resection margin is one of the most focused issues in surgical treatment. The definition of R0 resection has experienced a transition from a margin＞1cm to a margin＞1mm. The operative methods do not affect the resection margin status of CRLM. On the contrary, aggressive tumor biologies such as RAS mutation status, non-desmoplastic histopathological growth pattern, high tumor burden and bilateral distribution in the liver are related to high R1 resection rate. Compared with R1 resection, R0 resection can improve the prognosis of patients with RAS wild-type or low tumor burden, but cannot improve the prognosis of patients with RAS mutation or high tumor burden. For patients with major pathologic response to preoperative chemotherapy, resection margin status does not affect the survival. For patients with minor pathologic response to preoperative chemotherapy, the prognosis of R1 resection is worse than that of R0 resection. R1 resection for RAS wild-type CRLM patients with major pathologic response to preoperative chemotherapy, R1 resection with detachment of CRLM from major intrahepatic vessels and R1 resection for non-largest tumors of multiple CRLM are acceptable. Therefore, it is necessary to comprehensively consider various factors of patients to bring more survival benefits to CRLM patients.

Key words: colorectal liver metastases, resection margin, hepatectomy 

摘要： 外科治疗是结直肠癌肝转移（CRLM）最有效的治疗方式，手术切缘是外科治疗中的焦点问题。R0切除的定义经历了由切缘＞1 cm到＞1 mm的转变。手术方式并不会影响CRLM的切缘状态，相反，RAS基因突变、“非促纤维组织增生型”病理组织学生长模式、肿瘤负荷高和肝两叶受累等较具侵袭性的肿瘤生物学行为与较高的R1切除率相关。与R1切除相比，R0切除可以改善RAS基因野生型或低肿瘤负荷病人的预后，却不能改善RAS基因突变型或高肿瘤负荷病人的预后。对术前化疗病理学反应良好的病人，切缘状态不影响生存；对术前化疗病理学反应不佳的病人，R1切除的预后较R0切除更差。对术前化疗反应良好的RAS基因野生型CRLM病人的R1切除、从肝内大血管上剥离的R1切除以及多发性CRLM的非最大转移灶的R1切除均是可以被接受的。因此，需要综合考虑病人各方面因素，为CRLM病人带来更多的生存获益。

关键词: 结直肠癌肝转移, 手术切缘, 肝切除术