Differential immune cell densities in ductal carcinoma In-Situ and invasive breast cancer: Possible role of leukocytes in early stages of carcinogenesis

Objectives: to investigate immune cell densities in pre-neoplastic (dcis), cancer (idc) and control breast tissues. methods: a total of four preneoplastic, 104 cancer and 104 control samples were analyzed. morphological classification and prognostic scoring along with quantification of immune cells/mm2 was performed. data were entered and analyzed using spss version 16. correlation of immune cell densities with various tumour sub-types was investigated using paired t-test and anova. a p-value of <0.05 was considered as significant. results: our data show increased infiltration of lymphocytes (mean lymphocytes = 287.6cells/mm2) as well as myelocytes (mean lymphocytes = 117.1cells/mm2) in pre-neoplastic tissues. this infiltration was significantly high compared to cancer (p-value<0.001) as well as control tissues (p-value <0.001). moreover, we report increased infiltration of lymphocytes in cancer tissues compared to controls (p-value<0.001). there was no difference in lymphocyte densities within various tumour sub-types (all p-values >0.05). conclusion: leukocytes may play a role in early stages of breast carcinogenesis.