The Relationship Between Intratumor Bacteria And Tertiary Lymphoid Structures And Its Clinicopathological Significance In Invasive Ductal Carcinoma Of The Breast

Purpose:To evaluate the relationship between intratumoral bacteria(ITB)and tertiary lymphoid structures(TLS)of invasive ductal carcinoma(IDC)and its clinicopathological significance.Methods:124 female IDC,32 cases of ductal carcinoma in situ(DCIS),31 cases of chronic breast inflammation and 25 cases of accessory breast surgery were collected as the study objects.Immunohistochemistry of lipopolysaccharide(LPS)and lipoteichoic acid(LTA)and fluorescence in situ hybridization of 16s rRNA bacterial probe were used to observe and evaluate the ITB in these tissue samples,and the correlation between ITB and the formation of TLS and the clinicopathological characteristics of IDC were analyzed.Results:1.The positive rates of ITB in IDC,DCIS,accessory breast and chronic inflammation of the breast were 87.1%(108/124),93.8%(30/32),60.0%(15/25)and 100%(31/31),respectively.There was statistically significant difference in the positive rates of ITB in the four groups of lesions(χ2=21.734,P<0.001).2.53.2%(66/124)of IDC cases showed the formation of TLS in the tumor stroma;There was no statistically significant difference in the incidence of TLS between IDC of ITB positive group(55.6%,60/108)and IDC of negative group(37.5%,6/16)(χ2=1.825,P=0.177);In estrogen receptor(ER)and progesterone receptor(PR)negative IDC,the incidence of TLS in the ITB-positive group was 68.8%(22/32)and 67.4%(29/43),respectively,which were higher than that in the ITB-negative group 12.5%(8/32)and 9.3%(4/43),respectively(P=0.003,P=0.005);The incidence of TLS in LPS positive group and negative group was 64.9%(48/74)and 36.0%(18/50)respectively,the difference was statistically significant(χ2=9.986,P=0.002);The incidence of TLS in the LTA positive group and the negative group was 91.7%(11/12)and 49.1%(55/112)respectively,the difference was statistically significant(χ2=7.886,P=0.005).3.In terms of the relationship between ITB and IDC’s clinicopathological characteristics,the positive rate of ITB decreased with the increase of histological grading(P=0.007);The positive rate of ITB in ER or PR positive group was higher than that in ER or PR negative group(P=0.005 for ER and P=0.015 for PR,respectively);Among the different molecular types of IDC,the positive rate of ITB in Luminal A type was the highest(97.8%),and that in HER2 overexpression type was the lowest(60%)(P<0.001).Conclusion:In most IDC cases,there are ITBs dominated by gram-negative bacteria,and the ITB positive rate of hormone receptor positive IDC is the highest;There is no correlation between ITB and the formation of TLS in hormone-receptor positive IDC,but it may be related to the formation of TLS in hormone-receptor negative IDC;No effect of ITB on lymph node metastasis and clinical staging of breast cancer was found.