The epidermal growth factor receptor (EGFR) is a promising target for anticancer therapy because it is expressed or highly expressed in a variety of tumors, including NSCLC.Furthermore, high levels of EGFR expression have been associated with a poor prognosis in lung cancer patients in several studies. EGFR-targeted cancer therapies are currently being developed; strategies include inhibition of the intracellular tyrosine kinase domain of the receptor by small molecules such as gefitinib (Iressa \[ZD1839\]; AstraZeneca, Wilmington, DE). Iressa is an orally active, selective EGFR tyrosine kinase inhibitor that blocks signal transduction pathways implicated in the proliferation and survival of cancer cells.
