As we enter an unprecedented era of
personalized medicine,
molecular targeted therapies have the potential to induce improved survival outcome in patients with
non-small cell lung cancer (NSCLC). However, a significant percentage of oncogene-driven NSCLC patients will relapse even after definitive treatment, whereas chronic and durable response to targeted
therapies is a less common event in advanced-stage
lung cancer. This phenomenon could be attributed to
minimal residual disease (MRD), defined as a population of disseminated
tumor cells that survive during the course or
after treatment, eventually leading to recurrence and limiting patient survival.
Circulating tumor DNA (ctDNA) is a powerful
biomarker for MRD detection and monitoring and is a non-invasive approach of treating
cancer, and especially NSCLC, based on a real-time assessment of the
tumor genomic landscape. In this review, we present the key findings of studies that have used ctDNA with regard to its prognostic value and in respect to the most common druggable driver mutations of genes in NSCLC, such as
epidermal growth factor receptor (EGFR),
anaplastic lymphoma kinase (ALK), c-ros oncogene 1 (ROS1), rearranged during transfection (RET), Kirsten rat
sarcoma virus (KRAS), B-Raf proto-oncogene (BRAF), and mesenchymal epithelial transition factor receptor (MET).