EGFR and colonic neoplasm: Therefore, EGFR is a key participant in the development of many cancers (such as colon cancer, non-small cell lung cancer, breast cancer, head and neck cancer and ovarian cancer)56 and has become an important drug target.57 At present, targeted drugs for EGFR mainly include small tyrosine kinase inhibitors (TKIs) and monoclonal antibodies (mAb), which have been developed and successfully used in clinic.52 The mechanism of tyrosine kinase inhibitors and anti-EGFR monoclonal antibodies in cancer cells is shown in Fig. 3.