Clinicopathologic Features Of Ductal Carcinoma In Situ With Microinvasive Of Breast

Objective: Ductal carcinoma in situ with microinvasive(DCIS-MI)is considered to be the intermediate stage from ductal carcinoma in situ(DCIS)to invasive ductal carcinoma(IDC),whose clinicopathological and prognostic features remain controversial.The purpose of this study was to analyze the difference in clinicopathological features between DCIS-MI and DCIS and early invasive carcinoma which is on stage T1 through clinical observation.Methods: A retrospective study is performed involving 1886 cases diagnosed as DCIS or DCIS-MI or IDC from Jan 2014 to Dec 2018 in the Breast Disease Diagnosis and Treatment Center of Hebei Cancer Hospital.All patients are divided into five groups according to the diagnosis,DCIS group,DCIS-MI group,T1 a group,T1 b group and T1 c group,and each of them has 308 cases,92 cases,111 cases,343 cases and 1032 cases respectively.The patients in each group are compared for clinicopathological characteristics including age,menopausal status,surgical mode,lymph node status,molecular markers,etc,so as to obtain the clinicopathological characteristics of DCIS-MI.Results: A total of 1886 patients,ranging in age from 22 to 86 years,are selected in this study with a median age of 51 years.The breast conserving rate of the DCIS-MI group is about 5.4%,and that of the DCIS group is 17.2%,which is significantly higher than that of the DCIS-MI group.The lymph node metastasis rate in the DCIS-MI group is 4.5%.The lymph node metastasis rate in the DCIS group is 0%,which is significantly lower than that in the DCIS-MI group.However,the difference in tumor diameter,number of tumors,ER,PR,HER2 and Ki67 expression and molecular typing between the two groups is not statistically significant.There are 36 patients(39.1%)with high Ki67 expression in the DCIS-MI group,40 patients(36%)in the T1 a group,190 patients(55.4%)in the T1 b group,and 688 patients(66.7%)in the T1 c group.There is no difference in Ki67 expression between DCIS-MI and T1 a,but the proportion of high Ki67 expression in T1 a,T1b and T1 c groups gradually increases,and the difference is statistically significant.There are 42 patients(61.8%)with positive HER2 in the DCIS-MI group,29patients(31.2%)in the T1 a group,66patients(22.6%)in the T1 b group,and 231patients(25.4%)in the T1 c group.The proportion of HER2 positive patients in the DCIS-MI group is significantly higher than that in the T1a-b-c group.However,there is no significant difference in the expression of ER,PR and the lymph node metastasis rate in DCIS-MI,T1 a,T1b and T1 c.Conclusion: The clinicopathological features of DCIS-MI are similar to those of DCIS and T1 a,but significantly different from those of T1c.