title: Erlotinib usage after prior treatment with gefitinib in advanced non-small cell lung cancer: A clinical perspective and review of published literature.
abstract: Erlotinib and gefitinib are among the most widely researched, used and available molecularly targeted therapies for treatment of advanced non-small cell lung cancer (NSCLC). They are both tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR). In the past decade, there have been reports on clinical benefit from use of erlotinib after gefitinib failure in NSCLC patients. A review of published literature on this focussed topic is provided herein. Pooled analysis of published literature shows that majority of patients were female (60.6%), non-smokers (64.5%), had adenocarcinoma histology (88.3%) and were of East Asian ethnicity (92.3%). Presence of sensitizing EGFR mutation was detected in 48.4% of subjects. Disease control rates with prior gefitinib therapy and with subsequent erlotinib treatment were 79.4% and 45.4% respectively. Based upon our review, the most important predictive factor for clinical benefit from erlotinib identified was previous response to gefitinib. The exact explanations for the potential benefit from erlotinib use in this patient population is still not known and further studies are required to determine the role of molecular mechanisms especially those related to resistance to initial EGFR TKI therapy.
authors.affiliation: Navneet Singh, Aditya Jindal, Digambar Behera, Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Navneet
authors.initials: N
authors.lastname: Singh
authors.affiliation: Navneet Singh, Aditya Jindal, Digambar Behera, Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Aditya
authors.initials: A
authors.lastname: Jindal
authors.affiliation: Navneet Singh, Aditya Jindal, Digambar Behera, Department of Pulmonary Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Digambar
authors.initials: D
authors.lastname: Behera
keywords: Epidermal growth factor receptor; Erlotinib; Gefitinib; Non-small cell lung cancer; Tyrosine kinase inhibitor