ER-D5 antigen in breast cancer

We measured an estrogen-receptor-associated protein (ER-D5), estrogen and progesterone receptors (ER;PgR) in samples obtained from 28 female patients with primary breast carcinoma. A correlation of r=0.79 was found between ER-D5 and ER values and between ER-D5 and PgR values in premenopausal woman. In postmenopausal women a correlation (r=0.75) was found only between ER-D5 and ER and not between ER-D5 and PgR. The measurement of this cytosolic protein may be a complementary tool in the management of breast cancer.