In recent years, some physicians treat leukopenia by granulocyte colony-stimulating factor (G-CSF) too, but it is reported that some solid tumor cells can secrete CSFs and/or expression of their receptors,[9] exogenous G-CSF receptor-positive CSFs may increase the rate of tumor metastasis and local recurrence rate,[10] so the security of G-CSF application is being questioned. This evidence concerns the gene CSF3R and neoplasm.