DKK1 and cancer: As shown in Figure 4C, the analysis revealed significantly higher serum DKK1 levels in the advanced cancer patient group (1863.5 pg/mL; 62.5–4902 pg/mL; n = 32) than in the control group (504.8 pg/mL; 62.5–1260 pg/mL; n = 17); the AUC was 0.78 (Figure 4D).