Colorectal cancer (CRC) is the leading cause of cancer death worldwide. CRC therapeutic strategies include surgical resection, chemotherapy, radiotherapy, and other approaches. However, patients with metastatic CRC have worse prognoses. In recent years, T-cell-based immunotherapy has elicited promising responses in B-cell malignancies, melanoma, and lung cancer, but most CRC patients are resistant to immunotherapy, chemotherapy, and targeted therapy. Immune checkpoint inhibitors have shown encouraging results in non-small cell lung cancer, melanoma, and other cancers, but immune checkpoint blockade is only effective for CRC subset with microsatellite instability. Other immunotherapies, such as cytokines, cancer vaccines, small molecules, oncolytic viruses, and chimeric antigen-receptor therapy, are currently in use against CRC. This review analyzes recent developments in immunotherapy for CRC treatment as well as the challenges in overcoming resistance.

大肠癌（CRC）是全球癌症死亡的主要原因。CRC治疗策略包括手术切除，化学疗法，放射疗法和其他方法。但是，转移性CRC患者的预后较差。近年来，基于T细胞的免疫疗法已在B细胞恶性肿瘤，黑色素瘤和肺癌中引发了令人鼓舞的反应，但大多数CRC患者对免疫疗法，化学疗法和靶向疗法均具有抵抗力。免疫检查点抑制剂已在非小细胞肺癌，黑色素瘤和其他癌症中显示出令人鼓舞的结果，但免疫检查点封锁仅对具有微卫星不稳定性的CRC亚群有效。目前正在使用其他免疫疗法来抵抗CRC，例如细胞因子，癌症疫苗，小分子，溶瘤病毒和嵌合抗原受体疗法。