A study by Wang et al. shows cancer tissues from 60 patients with mammary carcinoma to exhibit no CEACAM1 staining (12/60 patients 20%) or weak CEACAM1 expression (13/60 patients 21.7%) while the adjacent breast tissues show moderate to intense staining in most cases, without negative expression [63]. This evidence concerns the gene CEACAM1 and breast carcinoma.