Clinicopathological significance of CEACAM1 gene expression in breast cancer

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a cell adhesion molecule expressed in a variety of cell types. The role of CEACAM1 in breast cancer development and progression is largely unknown. Immunohistochemical analysis was used to examine CEACAM1 expression in breast cancer with long-term follow-up. CEACAM1 expression level in primary breast cancer was low or undetectable. In 65% of the cases, CEACAM1 expression within tumor tissue was lower than that in adjacent tissues. In 20% of the cases, CEACAM1 was negative. In 28.3% of cases, equivalent CEACAM1 expression level was detected in tumor and adjacent tissues. The expression level of CEACAM1 in tumor tissue was negatively correlated with patient mortality, while positively correlated with the expression level of ER+/PR+. CEACAM1 expression was not related with patients' age, pathological classification, lymphatic involvement and the size of tumor. The down-regulation of CEACAM1 was correlated with negative ER-/PR- and might be attributed to the malignant process of breast cancer. The prognosis of the patients with low CEACAM1 expression and high tumor pathological grade were poorer than those patients with high expression and low pathological grade, P < 0.05. Clinically, it is possible to predict the prognosis among the patients of breast cancer by measuring CEACAM1 gene expression in the tumor tissues.