KRAS and lung cancer: The Epidermal Growth Factor Receptor (EGFR) was the first antigenic target used as a guideline for targeted lung cancer therapy, followed by other targeting markers, such as KRAS (Kirsten rat sarcoma viral oncogene homolog) and fusion of EML4-ALK1 (echinoderm microtubule-associated protein-like 4 – anaplastic lymphoma kinase), along with other ongoing clinical trials, such as MET, BRAF, RET (Echinoderm Microtubule Associated Protein like 4-AL-Kinase 1) and ROS1 (receptor tyrosine kinase 1) [4].