The sensitivity (LoD) 3.5/4.2 ng/mL was higher than a commonlyused ligand binding assay for NSE (0.15 ng/mL); however, the sensitivityis comparable to other intact protein quantification methods for differentproteins and is more than adequate to achieve the 25 ng/mL cutofflevel for lung cancer.16,32,42. Here, ENO2 is linked to lung cancer.