Biopsie liquide et cibles thérapeutiques, enjeux actuels et futurs en oncologie thoracique

The liquid biopsy (LB) concept has recently radically changed the clinical care of metastatic NSCLC patients. A high number of oncologists use now this approach in a daily routine, according to some indications for the detection of activating or resistant mutations. In this context, different tests made from plasma DNA have been approved as companion diagnostic tests for tyrosine kinase inhibitors treatment. ALK rearrangement identified in tumor tissue is also an essential target for an available specific treatment in late stages NSCLC. As for EGFR, the practice of LB has been rapidly developed for ALK genomic alteration assessment (rearrangements or mutations). However, this very promising approach demonstrates certain limitations, and probably does not show the same development observed for the blood tests made for EGFR status evaluation to date. Beside for EGFR and ALK status determination, LB can be used for looking some genomic alteration which can be present on other genes of interest (ROS1, RET, NTRK, MET, BRAF, HER2, etc.) in metastatic NSCLC patients. For all genes, the evaluation of the different genomic alteration can be search by using dedicated approach targeted one gene or by using different panels of genes. Since the number of potential molecular targets for new drugs and for including patients in clinical trial increased, the next generation sequencing technologies are currently developed to be used from blood samples. The purpose of this review is to summarize the role of the LB in the taking care of late stage lung cancer patients, but also its limitations. Finally some new perspectives are detailed.