Estrogen and progesterone receptors in breast cancer: relationships to tumour histopathology and survival of patients.

Estrogen receptor (ER) and progesterone receptor (PR) concentrations were measured in the tumours of 399 cases of primary breast carcinoma. Histological type and histological grading was also analysed. The correlation between survival and histological grading was observed and found to be of high significance statistically. Longer survival of patients with ER- and/or PR-positive tumours was also observed, but the ER and PR prognostic value did not reach the same magnitude as histological alone. The prognostic accuracy in breast cancer, when histological grading, ER and PR were used together, failed to reach statistically significant values. A lower proportion of ER- and PR-positive tumours were found in histological grade III. The majority of the tumours belonging to specific histological variants of carcinoma were ER- and/or PR-positive. Relationships between ER, PR, menopausal status, and age were also noted. It was apparent that the prognostic value of PR concentrations in the tumour was more relevant than that of ER alone.