Shifting paradigms in non-small cell lung cancer: an evolving therapeutic landscape.

Globally, lung cancer is the leading cause of cancer-related mortality among both men and women, and while mortality associated with the disease has demonstrated relative stability over the years, evidence has suggested an increasing incidence and prevalence of the disease. Unfortunately, the diagnosis of lung cancer is often made late in the course of the disease, with almost 70% of patients presenting with locally advanced or metastatic disease at initial diagnosis. Non-small cell lung cancer (NSCLC) is the most common form of the malignancy, occurring in up to 85% of cases. There are 3 subtypes of NSCLC: squamous-cell carcinoma, adenocarcinoma, and large-cell carcinoma. Enhanced understanding of the pathophysiology of NSCLC has led to substantial improvements in diagnostic, prognostic, and therapeutic interventions for NSCLC. The discovery of targetable molecular alterations in genes, such as epidermal growth factor receptor (EGFR), has driven the evolution of targeted therapies for NSCLC and shifted treatment paradigms for the disease. This article will summarize the epidemiology and pathophysiology of NSCLC, its associated gene mutations and biomarkers, and the approach to treatment, with a focus on patients whose tumors harbor EGFRactivating mutations.