Two hundred and eighty-eight primary breast tumours were examined for the presence or absence of oestrogen (REc) and progesterone (RPc) receptors. Analysis has shown a relative interdependence between the steroid receptor status of primary breast cancer and other prognostic variables such as histological grade, lymphocytic infiltration and tumour elastosis. There were significant associations between epithelial cellularity, stromal fibrosis and the value of REc in those tumours in which the receptor was present. Cellularity and fibrosis were unrelated to the presence or absence of oestrogen receptor. By contrast, neither the presence or absence nor the value of RPc could be related to cellularity or fibrosis. The value of REc and RPc analysis as an indicator of prognosis was examined in a sub-group of 175 patients receiving no additional treatment following mastectomy. Overall relapse-free survival (RFS) was no different for those patients with receptors compared to those without them (REc P = 0.11, RPc P = 0.7). There was no difference in RFS of receptor positive and negative tumours when the axillary node status was taken into account.