Secretion of epidermal growth factor by macrophages associated with breast carcinoma.

By means of a cytokine release assay we have shown that in cell populations derived from primary breast carcinoma, epidermal growth factor (EGF) is secreted by cells with the characteristic morphological and immunophenotypic profile of activated macrophages (positive for CD68, CD16, CD25). EGF secretion was observed in 11 (31%) of 35 primary tumours. Secretion of EGF by normal or malignant epithelial cells was not observed. We found no association between EGF secretion by the primary tumour and recognised clinical indices of prognosis.