GRP and small cell lung carcinoma: For NSCLC, the panel of Pro-GRP, CEA, CYFRA 21-1, SCC-Ag, and NSE achieved the highest AUC of 81.1% (sensitivity = 74.5% and specificity = 78.8%), and CYFRA 21-1 + Pro-GRP + NSE performed best for SCLC (AUC = 97.3%, sensitivity = 88.8% and specificity = 98.9%).