Preparing for tomorrow: molecular diagnostics and the changing nonsmall cell lung cancer landscape.

Over the last 10 to 15 years, the landscape of lung cancer has changed dramatically. Where cancers were previously described rather simplistically according to histological subtype, now molecular understanding of tumors has particularly resulted in segmentation of nonsmall cell lung cancer into many different subtypes. A multidisciplinary approach integrating a molecular testing algorithm that ideally includes reflex testing at diagnosis is recommended. This offers clinicians the opportunity to target treatment according to subtype. Identifying patients with rearrangements, such as those associated with the echinoderm microtubule-associated protein-like 4 (EML-4) anaplastic lymphoma kinase (ALK) fusion gene (the major focus of this paper) has allowed clinicians to tailor therapy to target these mutations. The challenge that faces clinicians treating lung cancer is how best to implement the science that sits behind these targeted therapies in clinical practice through the identification of appropriate patients. Precision medicine can lead to the choice of the right medicine for the right patients and is proving to be a better approach than treating unselected patients with systemic chemotherapy.