KRAS and neoplasm: Notably, the AUC for TP53 was significantly larger when using blood than tumor samples (0.835 vs 0.706, P = 0.040), and the AUCs for KRAS (0.801) and TP53 (0.835) in ctDNA were higher than for the routine clinicopathologic characteristics (0.511–0.675; Additional file 1: Fig. S2).