Most of the mAbs against growth factor receptors target a family of receptor tyrosine kinases (RTKs) as EGFR, HER2, HER3, and c-met, etc. These mAbs are approved for different cancers, including metastatic colorectal cancer (CRC), non-small-cell lung carcinoma (NSCLC), and squamous cell carcinoma (SCC). The gene discussed is EGFR; the disease is metastatic colorectal cancer.