Drug resistance and its significance for treatment decisions in non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) constitutes about 85% of all lung cancers. Approximately 50% of patients diagnosed with NSCLC present with advanced disease (stage III or IV) that is not amenable to curative treatment. The number of patients with stage IIIB or IV disease who are alive at 1 year after diagnosis has increased from 10% in the untreated population in the early 1980s to 50% in patients with a good performance status receiving treatment today. However, those statistics remain dismal, and the two dominant reasons are the large number of patients diagnosed with advanced-stage disease and the observed primary or secondary resistance to current therapies. The present article addresses the question of drug resistance in lung cancer, focusing on subjects that are currently topical and under intense scrutiny.