Abstract
Lung cancer, a major global public health issue, is the leading cause of cancer death in the United States. In spite of the importance of this disease, there has been only a 3% improvement in 5-year survival over the past 30 years. While there have been some recent promising developments in screening and diagnosis, there is an urgent need to improve on therapy so that more people can be cured or have a longer life. In the field of biomarkers for non–small cell lung cancer we are beginning to characterize lung tumors by their molecular signature and design therapy accordingly. This article will address biomarkers for non–small cell lung cancer, with an emphasis on those that are either already used in clinical practice or being studied in current clinical trials. Epidermal growth factor receptor (EGFR), Kirsten rat sarcoma (KRAS), excision repair cross-complementation group 1 (ERCC1), ribonucleotide reductase 1 (RRM1), and echinoderm microtubule-associated protein-like 4–anaplastic lymphoma kinase (ELM4-ALK) will be discussed. For each marker, we will address normal function in the cancer cell; impact on function when it is present, absent, or mutated; testing for the marker; incidence or frequency of the marker as well as characteristics (if known) of patients more likely to be positive for the marker; and function of the marker as prognostic, predictive, or both. We will also address implications for the advanced practitioner.
