CEACAM5 and chronic obstructive pulmonary disease: Comparison of ROC curves for the most prospective tumor markers, such as CEA, CYFRA 21-1, SCC and CA-62 for the entire NSCLC patient’s cohort against all healthy controls and COPD patients (Figure 3) showed a valid difference in the areas under the curve between CA-62 (AUC =0.981) and other TM (area difference AUC = 0.21 - 0.7).