CEACAM5 and neoplasm: In the univariate analysis, tumor size (≤1.8 cm vs. 1.9–3.1 cm OR = 6.764, P < 0.001; vs. ≥3.2 cm OR = 2.022, P = 0.007), age (≥40 years vs. < 40 years, OR = 2.087, P = 0.044), pre-NCRT clinical T stage (OR = 0.731, P = 0.031), pre-NCRT clinical N stage (OR = 0.550, P = 0.016), distance from the anal verge (OR = 0.919, P = 0.018), and post-NCRT CEA (OR = 0.381, P < 0.001) were significantly associated with pCR in LARC patients.