Abstract: Objective Analyze the clinicopathological features of invasive ductal carcinoma  with ductal carcinoma in situ(IDC+DCIS) and  invasive ductal carcinoma(IDC).
Methods 335 breast cancer patients treated in the Department of Thyroid and Breast Surgery,Maternal and Child Hospital of Hubei Province from 2016 to 2020 were adopted,including 123 patients in the IDC+DCI group and 212 patients in the IDC group.SPSS 23.0 software was used for statistical analysis to compare the tumor size,lymph node stage,and the expression of ER,PR,HER-2,Ki-67%,CK5/6 and other molecular indicators between the two groups.
Results The expression of HER-2 in the IDC+DCIS group was higher than that in the IDC group(40.7% vs 25%,P=0.003),while the positive rate of CK5/6 was significantly lower than that in the IDC group(10.4% vs 42.6%,P=0.00).In addition,the IDC group had a higher rate of triple negative breast cancer(23.3% vs 9.8%,P=0.02).
Conclusion Compared with invasive carcinoma,invasive ductal carcinoma with carcinoma in situ shows different immunohistochemical phenotype.Whether this difference in phenotype indicates that the two cancers infiltrate through different pathways is worthy of further research.

Key words: breast neoplasms, breast carcinoma in situ, immunohistochemistry