Oestrogen and progesterone receptors and their relationship to histological grades of epithelial tumours of the magnum region of the oviduct of the domestic fowl

Tumours of the proprial tubular glands of the magnum region of the oviduct of the domestic fowl ( Gallus domesticus) were found to contain receptors for oestrogen and progesterone. The distribution of the receptors in the cytosol and nucleus of the tumour cells was similar to that of the normal magnum under oestrogen stimulation. Receptor content showed a positive correlation with increasing clinical stage and histological grade, i.e., malignancy and undifferentiation of the tumours. These tumours are unusual for hormonally responsive tumours in that their receptor mechanism remains intact with loss of differentiation.