Multivariate logistic regression analysis revealed that differentiation (OR 0.056 (95% CI 0.004–0.889), p = 0.041), MCV (OR 0.615 (95% CI 0.401–0.942), p = 0.025), and CEA (OR 1.639 (95% CI 1.126–2.386), p = 0.010) were the predictors of tumor response to preoperative CRT. Here, CEACAM5 is linked to neoplasm.