Oestrogen receptor concentration and macrophage infiltration in human breast cancer.

Oestrogen receptor concentration and percentage macrophage content were estimated in 40 human primary breast cancers. Macrophages were identified by Fc (IgG) receptor expression and by the presence of a macrophage-associated antigen. A significant inverse correlation between receptor concentration and macrophage content was found, and this was strengthened by correcting receptor level for tumour cellularity.