[The estrogen receptor/progesterone receptor quotient as an index of the transcriptional activity of estrogen receptors in breast cancer]. / El cociente receptores de estrógenos/receptores de progesterona como índice de la actividad transcripcional de los receptores de estrógenos en el cáncer de mama.

ABSTRACT

BACKGROUND: The aim of this study was to determine whether the induction of progesterone receptors (PR) for estrogen receptors (ER) in variable in breast cancer, whether it differs among pre and post menopausal women and whether the ER/PR quotient may be an index of tumoral biology. METHODS: The ER and PR content was determined by enzyme immunoassay in 814 breast tumors and the ER/PR quotient was calculated in the ER+PR+ tumors (n = 395). RESULTS: ER/PR values < 1 were more frequent in premenopausal women (66%) than in post menopausal women (38%). No influence was observed with regard to age. CONCLUSIONS: The highest ER/PR values were found in post menopausal women indicating decreased estrogen receptor transcriptional activity in this subgroup contrary to that found in premenopausal women.