Abstract: ObjectiveTo analyze expression levels of helper and regulatory T cells in peripheral blood in the patients with invasive micropapillary carcinoma(IMPC).MethodsA total of 21 IMPC patients were consecutively selected from January to December,2012.All cases were detected for regulatory T(Treg) cells(CD⁴CD25⁺ Treg and CD₊⁴ CD_F⁺oxp3²⁵+ Treg)and helper T cells(CD⁺³,CD⁺⁴,CD⁺⁸,CD⁺⁴/CD⁺⁸)in the peripheral blood and lesion supernatant with flow cytometry.The results were compared with those of 24 patients with infitrating ductal carcinoma(IDC)and 27 patients with benign breast disease(control group)at the corresponding time period.ResultsThe expression levels of CD⁺³,CD⁺⁴ and CD⁺⁴/CD⁺⁸ in the IMPC group were significantly lower than those in the IDC and control groups,but the expression level of CD⁺⁸ in the IMPC group was significantly higher than that in the IDC and control groups(P<0.05 or P<0.01).Meanwhile,the expression levels of CD⁴CD25⁺ Treg and CD₊⁴ CD₂₅⁺ Foxp3⁺ Treg in the IMPC group were significantly higher than those in the IDC and control groups(P<0.05 or P<0.01).ConclusionThe helper and regulatory T cells are abnormally expressed in the peripheral blood and lesion tissues among the patients with IMPC,and the abnormal expression may be related to biological behavior and special clinical manifestation of IMPC.