Utility of IDH1 as a Serum Protein Biomarker for the Early Detection of NSCLC: A Multicenter In Vitro Diagnostic Clinical Trial.

We aimed to verify the expression status and diagnostic significance of IDH1 in NSCLC, especially during early stages. Serum IDH1 levels were measured by ELISA. A total of 1223 participants [660 patients with NSCLC, 276 healthy controls (HCs), 95 patients with benign pulmonary conditions (BPCs), 135 patients with other cancers (OCs) and 57 samples with interfering factors] were divided into a training cohort and a validation cohort according to three testing centers. The IDH1 concentrations in the NSCLC group were obviously higher than those in the control groups (P < 0.001). AUCs for discriminating NSCLC patients from controls (HC, BPC and OC) were 0.870 and 0.745 (sensitivity: 63.3% and 55.0%; specificity: 86.8% and 86.3%) in the training cohort and validation cohort, respectively. AUCs for discriminating stage 0-IA lung cancer patients from HCs were 0.907 and 0.788 (sensitivity: 58.6% and 59.1%; specificity: 92.9% and 89.3%) in two cohorts, respectively. IDH1 exhibited specificity for NSCLC and had no diagnostic value for other common cancers. Furthermore, IDH1 was significantly reduced in postoperative serum. IDH1 exhibits clinical utility as a serum protein biomarker for the early diagnosis of NSCLC.