Chemokines CXC chemokine ligand (CXCL) 10, CXCL9, CC chemokine ligand 5 gene (CCL5), Fcgamma receptor 3A (FCGR3A), and CC chemokine receptor 2 (CCR2) owned degree values not less than 10 were deemed as core genes differentially expressed between PTC with and without HT, all which were upregulated in tumor tissue samples of PTC with HT compared with those without HT. The gene discussed is CCL5; the disease is hematocrit.