Ghilardi et al. reported that the presence of at least one G allele in patients with stage I or II BC at the time of diagnosis enhances their risk of metastasis by a factor of 2.67 compared with patients diagnosed in the same stage but homozygous for allele A. However, they could not confirm any associations between the presence of a CCL2 G allele and vascular or lymph node invasion. Here, CCL2 is linked to breast cancer.