Test Details: Lung Cancer is the leading cause of cancer death worldwide. Chemotherapy for non-small cell lung carcinoma (NSCLC), accounting for 85%of lung cancer cases, remaining marginally effective. Epidermal growth factor receptor (EGFR) tyrosine kinase (TK) inhibitor, gefitinib (Iressa), was approved in several countries for the treatment of NSCLC. Mutations in the EGFR gene correlate with clinical responsiveness to the TK inhibitor. In majority of patients with highly responsive tumors, the tumor contains somatic mutation of the EGFR gene. Screening for the mutation in the lung cancer helps to stratify patient’s responsiveness to Gefitinib and Erlotinib.