The CEA clearance pattern remained a significant predictive factor for TRG (OR, 4.37; 95% CI, 1.44–13.23; P = 0.009; Table 7), tumor downstaging (OR, 4.28; 95% CI, 1.47–12.43; P = 0.008; Table 5), and pCR (OR, 5.22; 95% CI, 1.02–26.60; P = 0.047; Table 6). Here, CEACAM5 is linked to neoplasm.