As an integral part of precision medicine, the role of liquid biopsy in non-small cell lung cancer (NSCLC) is highlighted in this special issue of Journal of Thoracic Disease with a selection of articles written by a panel of eminent experts. There are many reasons to consider NSCLC as a potential ideal field of application for liquid biopsy: first, the availability of a non-invasive and repeatable method for diagnosis and disease monitoring could be extremely useful in NSCLC patients, considering that physicians have difficulty in obtaining an adequate tumor tissue with standard procedures and that patients are not always suitable to receive a re-biopsy; second, analysis of circulating tumor cells (CTCs) or circulating tumor DNA (ctDNA) which originate from all potential lesions could overcome the disadvantages of single site biopsy; last but not least, recent stuxdies showed either that CTCs count may have a prognostic value in NSCLC or that molecular characterization of CTCs/ctDNA may permit the assessment of druggable alterations.
