Colorectal cancer (CRC) is the fourth most common cause of cancer and mortality worldwide and is the third most common cancer in men and women. Surgery, radiotherapy, and chemotherapy are conventionally used for the treatment of colorectal cancer. However, these methods are associated with various side effects on normal cells. Thus, new studies are moving towards more effective and non-invasive methods for treatment of colorectal cancer. Targeted therapy of CRC is a promising new approach to enhance the efficiency and decrease the toxicity of the treatment. In targeted therapy of CRC, antibody fragments can directly inhibit tumor cell growth and proliferation. They also can act as an ideal carrier for targeted delivery of anticancer drugs. In the present study, the structure and function of different formats of antibody fragments, immune-targeted therapy of CRC using antibody fragments will be discussed.

结直肠癌（CRC）是全球第四大最常见的癌症和死亡原因，也是男女第三大最常见的癌症。外科手术，放射疗法和化学疗法通常用于治疗大肠癌。但是，这些方法与对正常细胞的各种副作用有关。因此，新的研究正在朝着更有效和非侵入性的方法治疗结直肠癌。CRC的靶向治疗是一种有前途的新方法，可以提高治疗的效率并降低其毒性。在CRC的靶向治疗中，抗体片段可以直接抑制肿瘤细胞的生长和增殖。它们还可以作为靶向递送抗癌药物的理想载体。在本研究中，不同格式的抗体片段的结构和功能