CEACAM5 and lymphopenia: To control the possible confounding of the main effects of chemotherapy-associated lymphopenia <0.66 × 109/L/0.91 × 109/L on DFS/OS, respectively, the clinicopathological factors (pretreatment albumin, pretreatment CEA, differentiation, sex, age, location and stage) and duration of lymphopenia <1.0 × 109 L were further adjusted for in the multivariate cox regression model.