CXCL12 and breast cancer: In the present study, we demonstrated that serum SDF-1 levels have diagnostic value in cats with mammary carcinoma and determined that the best cut-off value to discriminate cats with mammary carcinoma from healthy ones (≥ 2 ng/ml) is close to the one reported for breast cancer patients [40, 43], reinforcing the idea that FMC is a suitable cancer model.