Circulating estradiol defines the tumor phenotype in menopausal breast cancer patients

Abstract

Objective: To correlate circulating hormone levels with the clinical and biological features of the tumors in menopausal breast cancer patients.

Design: Circulating hormone levels were measured in 161 previously untreated menopausal breast cancer patients within 72 h of their planned surgery. The obtained hormone levels were correlated with tumor size, histological and nuclear grade, histological score, axillary nodal status, DNA-ploidy and Ki67-, c-erb-B2-, p53, Bax-, VEGF- and Nup88-expression.

Results: The only statistically significant correlations found between circulating hormone levels and all tested variables were an inverse one between estradiol and the expression of the apoptosis-associated Bax gene (p=0.009), and again an inverse correlation between estradiol and the expression of c-erb-B2 (p=0.04). When comparing hormone levels with each other, a significant correlation between estradiol and progesterone (p<0.0001), an inverse one between estradiol and FSH (p=0.04) and a direct one between LH and prolactin (p=0.001) were found.

Conclusion: Higher circulating estradiol levels in postmenopausal breast cancer patients are associated with molecular features usually defining a biologically less aggressive tumor phenotype.