Thalidomide Enhances Clinical Efficacy of Cetuximab Combined With Standard Chemotherapy for Left Colorectal Cancer

Inclusion Criteria: 1. Patients with RAS and BRAF wild-type IV unresectable left colorectal cancer confirmed by pathology and tissue/cytology and genetic testing; 2. Physical state is good: PS 0-2; 3. Expected survival of more than 3 months; 4. Aged 18-75 years old; 5. Have not received systematic chemotherapy before; 6. Did not receive cetuximab treatment; 7. Liver, kidney and bone marrow functions are basically normal; 8. The clearance period of chemotherapy and molecular targeted therapy is more than 4 weeks; 9. Voluntary participation in the group, good compliance, can cooperate with the experiment observation, and sign the written informed consent. Exclusion Criteria: 1. Patients with severe dysfunction of vital organs (heart, liver, kidney); 2. Patients with other malignant tumors; 3. Patients who are pregnant or breastfeeding (women of childbearing age need to check pregnancy test); 4. In the active phase of acute or chronic infectious diseases; 5. People with a clear history of drug allergy or allergic constitution; 6. Patients participating in other clinical trials; 7. Other conditions in which the patient was considered inappropriate to participate in the study.