Wang et al. compared the concentrations of 10 chemokines and chemokine receptors (CXCL5, 7, 8, 12, CCL2, CXCR4, CCR2, 5, 7 and atypical chemokine receptor DARC/ACKR1) in the serum of 148 patients diagnosed with benign breast changes, epithelial proliferation (present only or with atypia), in situ carcinoma and invasive carcinoma. Here, CXCR4 is linked to invasive carcinoma.