EGFR and non-small cell lung carcinoma: For example, gefitinib, the first EGFR tyrosine kinase inhibitor (TKI) developed, was approved by the US Food and Drug Association (FDA) in 2003 to treat NSCLC,22 followed by the FDA approval of erlotinib for NSCLC in 200423 and lapatinib for the treatment of ERBB2 positive breast cancer in 2007.24