Cytohistochemical studies on estrogen receptors of breast cancer tissue using an immunoperoxidase technique.

The estrogen receptors (ER) in breast cancer tissues were investigated in 122 patients using an immunoperoxidase method. ER (+) were evident in 77 of 122 patients (63.1 per cent). If classified according to pre- and postmenopausal subjects. ER (+) was seen in 61.4 per cent and ER (-) in 32.9 per cent before menopause, and ER (+) in 65.4 per cent and ER (-) in 30.8 per cent after menopause with no marked difference between the two. If classified according to histological type, ER (+) was seen in 72.3 per cent of those with papillotubular carcinoma and in 62.0 per cent of those with scirrhous carcinoma, whereas ER (-) was seen in 44.9 per cent of those with medullary tubular carcinoma. ER (+) was seen in carcinoma with apocrine metaplasia, lobular carcinoma and Paget's carcinoma. Concerning the relationship between primary tumors and metastatic lymph nodes, ER (+) for both was seen in 20 of 41 patients (48.8 per cent) whereas ER (-) for both was found in 9 of 41 patients (22.0 per cent). Four patients with local recurrences had a positive ER (+) at the beginning of treatment, but the ER became negative after hormonal treatment and chemotherapy.