The proportion of patients in the CA15-3-high group was significantly higher than that in the bone metastasis (p < 0.0001) and the proportions of patients in the CEA-high and CA15-3-high groups were significantly higher than that in the visceral metastasis (p = 0.0006 for CEA and p < 0.0001 for CA15-3). This evidence concerns the gene CEACAM5 and bone metastasis.