Colorectal cancer is one of the common malignant tumors. 60%-70% of colorectal cancer patients will develop liver metastases, of which about 25% are concurrent liver metastases and 35%-45% are heterochronic liver metastases. The median survival time of untreated patients is 6-18 months. However, in the last decade, with the widespread use of chemotherapeutic drugs (Oxaliplatin and Irinotecan) and targeted drugs (Cetuximab and Bevacizumab) in clinical practice, the promotion of surgical resection techniques for liver metastases and the proposal and application of comprehensive perioperative treatment modalities, the treatment outcome and survival of patients with liver metastases from colorectal cancer have significantly The treatment outcome and survival of colorectal cancer patients with liver metastases have improved significantly. However, among many treatment methods, surgical resection of colorectal cancer liver metastases is the most effective and potentially curative treatment method at present. Surgical resection of colorectal cancer liver metastases is currently a hot topic in common tumor research. The role of surgical resection in colorectal cancer liver metastases: For colorectal cancer liver metastases, about 20% of patients have the chance of surgical resection when liver metastases are found. A number of studies in France and other countries 10 years ago have shown that the 5-year survival rate of patients with colorectal liver metastases can reach 35%-40% after surgical resection. In contrast, the 5-year survival rate is generally <5% in patients treated with any non-surgical method. Factors affecting the outcome of surgery include the number, size, simultaneity/heterochronicity of the liver metastases, whether the resection is radical, the presence of extrahepatic metastases and the level of tumor markers. Surgical resection has a significant survival advantage over other treatments, and surgical resection of liver metastases is the best treatment modality to achieve long-term survival for patients who are able to undergo surgical resection. Patients who have the chance of surgical resection are still very limited. Two principles should be followed in selecting patients for surgical resection: (1) safety of surgery: whether the residual liver can maintain normal liver function after surgical resection of liver metastases, it is generally accepted that the residual liver should be >30%, and a higher percentage of the residual liver should be retained for patients who have undergone chemotherapy before surgery to avoid liver insufficiency after surgery. The latest study reported that the mortality rate of colorectal cancer liver metastases after surgical resection is close to 0%. (2) Completeness of surgery: Surgery should be able to remove all metastatic lesions inside and outside the liver in order to achieve radical resection. It is because only radical resection can the patient get an extended survival time from the surgery. Therefore, we should learn from foreign experience in the treatment of liver metastases from colorectal cancer, change the understanding of liver metastases from colorectal cancer in terms of staging and selection of treatment, improve the surgical resection rate of liver metastases, and then prolong the survival time of patients with liver metastases. 2.Surgical strategy for inoperable liver metastases: Although the efficacy of resection of liver metastases has been confirmed by many studies, after all, only 20% of patients have the chance of surgical resection when liver metastases are detected. The majority of patients will not have the opportunity for surgical resection due to the presence of multiple lesions in the left and right lobes or the small size of the residual liver after surgery, and the two principles of thoroughness and safety are not available at the time of detection of liver metastases. The main reason why liver metastases cannot be surgically resected is that the residual liver volume is insufficient, and if surgical resection is used, the patient is likely to experience post-surgical liver failure. How to make patients who do not have the chance of surgery at the time of diagnosis, get the chance of surgery. Currently, the main methods used internationally are portal vein embolization and second stage resection.1 Portal vein embolization is done by ligation or embolization of the portal vein, which produces atrophy of the right lobe of the liver and hypertrophy of the left lobe of the liver, increasing the volume of the residual liver. This is usually done by surgical excision of the lesion in the left lobe of the liver and ligation of the right branch of the portal vein, with a second surgery – right hemicolectomy – performed in about 4 weeks. The surgical strategy described above allows for surgical resection in some patients who do not have access to surgery due to insufficient residual liver and reduces the risk after surgery. The new surgical strategy of portal vein ligation and second-stage resection can enable about 10% of patients, who have no chance of surgical resection, to get prolonged survival of these patients. 3. Neoadjuvant chemotherapy improves the resection rate of liver metastases: Although surgical resection has obvious advantages in the treatment of colorectal cancer, only 20% of patients may achieve radical resection. In the last decade, with the use of new chemotherapeutic agents and targeted drugs in clinical practice, the results of an increasing number of studies have confirmed that neoadjuvant chemotherapy can reduce the tumor size and increase the surgical resection rate in a proportion of patients with liver metastases. chemotherapy with Folfox or Folfiri is effective in 40% to 50% of patients with liver metastases. In an analysis of 2047 patients treated with neoadjuvant chemotherapy from 1988 to 2003 at the Paul Brousse Hospital in Paris, 14% of patients were treated with neoadjuvant therapy from inoperable to surgical resection. the Crystal and Opus study reported at ASCO and ESMO in 2008 showed that the combination of chemotherapy with Epiduo could The efficacy of Epiduo in combination with chemotherapy was shown to increase the efficacy of neoadjuvant therapy to 77%. The efficacy of Epiduo was correlated with the presence or absence of mutations in k-ras, the primary lesion of colorectal cancer. Testing for k-ras is necessary before choosing to use Epiduo. As the number of colorectal cancer patients increases, so does the number of colorectal cancer liver metastases. Colorectal cancer liver metastasis has its own biological characteristics and should be aggressively surgically resected for patients who can achieve radical surgical resection. For patients who do not have the chance of surgical resection, we should strive to obtain the chance of surgical resection through comprehensive treatment in the perioperative period. We should continue to learn the latest progress in this field and improve our understanding of liver metastasis of colorectal cancer for the benefit of patients with liver metastasis of colorectal cancer.