CEACAM5 and neoplasm: Multivariate analysis also showed the strongest independent prognostic factors predicting lower disease-free survival to be age (>60) (p = 0.036), preoperative CEA level (>5 ng/ml) (p = 0.032), tumor location (rectum) (p < 0.001), and pathologically confirmed T4 staging (p = 0.006).