%0 Journal Article
%T Critical issues in the clinical application of liquid biopsy in non-small cell lung cancer
%A Antonella Facchinetti
%A Cristina Poggiana
%A Mariangela Manicone
%A Rita Zamarchi
%J SCIE-indexed Journal
%D 2017
%R 10.21037/jtd.2017.07.28
%X On the road from the laboratory bench to the patient¡¯s bedside, an assay measuring a tumor marker must be evaluated in order to demonstrate its analytic and clinical validity (respectively: the assay accuracy and reproducibility, and its ability to identify a biologic difference that predicts patient outcome), and at the end its clinical utility (the results of the assay¡ªpositive or negative¡ªlead to a clinical decision that evidently improves patient outcome) (1). Thus, a tumor marker must encompass several levels of evidence in order to demonstrate its clinical utility, with the final aim to improve patient outcome, in terms of overall survival (OS), disease-free survival and quality of life, and obtain a more cost-efficient application of effective therapies. The Tumor Marker Utility Grading System (TMUGS) is a framework that establishes an agenda for evaluating the clinical utility of tumor markers, and describes five levels of evidence as ¡°categories that define the quality of data available on which the utility score is based¡±. These levels range from the weak level V evidence, derived from case reports and clinical examples, to the strongest level I evidence, ¡°the definitive demonstration of clinical utility, obtained by a single, high-powered, prospective, randomized, controlled trial or from a meta-analysis or overview of multiple, well-designed studies¡±, passing through intermediate degrees of evidence in levels II¨CIV (2)
%U http://jtd.amegroups.com/article/view/14582/html