Immunophenotype of the lymphoid cell infiltrates in breast carcinomas of low oestrogen receptor content.

Several studies of breast tumour histology and oestrogen receptor (ER) contents report an inverse correlation between the density of the stromal lymphoid cell infiltrate and the presence or concentration of ER. Using monoclonal antibodies to lymphoid cell surface markers we have examined the immunophenotype of the infiltrating lymphoid cells and related this to the tumour ER content. There is a significant inverse correlation between the presence of Leu7-positive cells, which includes a subpopulation of natural killer (NK) cells, and tumour ER content; this is possibly superimposed on the dilutional effect of macrophages and other infiltrating cells.