CTLA4 and malignant colon neoplasm: At present, molecular targets of colon cancer comprise EGFR, VEGF, ERBB2, BRAF, KRAS, PD-1, CTLA-4, NTRK etc. The targeted therapy of CRC patients displaying EGFR and EGFR-related pathway gene mutations can be divided into those using monoclonal antibodies and those using small molecule tyrosine kinase inhibitors (TKIs).