RRM2 and non-small cell lung carcinoma: The ROC curve analysis results showed that the diagnosis of NSCLC with CEA (area under the ROC curve (AUC): 0.903, cut-off value: 2.10 ng/mL, sensitivity: 0.845, specificity: 0.880, accuracy: 0.856) was better than that with RRM2 (AUC: 0.798, accuracy: 0.738).