Objective: To evaluate the role of regional lymphadenectomy in patients with colorectal cancer liver metastasis. Background: Lymph node status is 1 of the most important prognostic factors in oncologic surgery; however, the role of lymph node dissection remains unclear for colorectal cancer liver metastasis.

Lymph node status is a definite prognostic factor in oncologic surgery and significantly affects long-term survival, as reported by the tumor staging system of the International Union Against Cancer (IUCC), which is the most widespread classification of malignant tumors worldwide. Regional lymphadenectomy is already the standard procedure that completes hepatic resection in the case of carcinoma arising from the extrahepatic bile duct. However, the indication, extent, and role of lymph node excision are still a matter of discussion, and no clear guidelines exist in patients with colorectal cancer liver metastasis.

Inclusion Criteria:

1. first hepatectomy;
2. age <75 years;
3. absence of severe cardiovascular,pulmonary, or other associated diseases;
4. absence of other malignant disease;
5. absence of distant metastases secondary to colorectal cancer other than liver metastases (except a solitary peritoneal tumor that could be completely resected during hepatectomy); and
6. complete resection of liver metastases confirmed during surgery.

Exclusion Criteria:

1. HNPCC
2. FAP
3. patient who refuses perihepatic lymphadnectomy
4. medical condition in which surgery cannot be tolerated

Biopsy confirmed colorectal cancer with liver metastasis