Although afatinib is potentially effective for the treatment of CRC cells resistant to anti-EGFR mAb [8], the strong and irreversible covalent bond formation between afatinib and EGFR may also appear in normal cells, which may increase afatinib’s uncomfortable adverse events, such as pulmonary, cutaneous, and gastrointestinal (GI) symptoms [16]. The gene discussed is EGFR; the disease is colorectal carcinoma.