Circulating Tumor DNA for Mutation Detection and Identification of Mechanisms of Resistance in Non-Small Cell Lung Cancer.

Targeted therapies have changed the treatment landscape of non-small cell lung cancer over the past decade. Analyses of cell free circulating tumor DNA (ctDNA) provide a non-invasive and robust approach for cancer diagnosis and prognosis, real-time monitoring of treatment response, and the identification of appropriate therapeutic targets based on the detection of tumor genetic aberrations. Recent improvements in the sensitivity, specificity, and feasibility of ctDNA detection assays allow the possibility for implementation into clinical practice. This review will focus on key studies using ctDNA analysis in early lung cancer detection, prediction of treatment response, monitoring minimal residual disease and disease relapse, and the identification of resistance mechanisms. We explore how ctDNA can be used as a surrogate for tissue biopsy and an integral biomarker in the clinical management of patients with non-small cell lung cancer.