Epidermal growth factor receptor inhibitors in non-small cell lung cancer.

Aberrant epidermal growth factor receptor (EGFR) signalling contributes to neoplastic transformation and EGFR inhibition by antibodies and small molecules inhibits cancer cell proliferation and survival. In previously treated patients with non-small cell lung cancer, the administration of gefitinib and erlotinib are associated with objective tumour response rates of 8-19%. However, only erlotinib has been shown definitively to improve patient survival. The likelihood of benefit may be determined by the presence of specific genotypic abnormalities in EGFR or downstream pathway components. Additional evaluation to determine optimal dose/schedule of the agents combined with standard treatments and with other targeted agents in appropriately selected patients are areas of active research.