Serum Estradiol Level and Risk of Breast Cancer During Treatment With Raloxifene

Abstract

Measurement of estradiol level by sensitive assay in postmenopausal women identifies those at high risk of breast cancer who may benefit most from raloxifene. If confirmed, this suggests that measuring estradiol and treating women with high estradiol levels could substantially reduce the rate of breast cancer among postmenopausal women.

Risk factors for breast cancer in older women: the relative contribution of bone mineral density and other established risk factors

“…Pre-existing vertebral fractures were identified on lateral spine radiographs at baseline using a semi-quantitative scale for each vertebra [16,17]. Serum estradiol was measured at MORE baseline by a central laboratory, using a double-antibody procedure [18]. Estradiol levels less than 5 pmol/l were below the limit of accurate quantification.…”

Bone mineral density and risk of postmenopausal breast cancer

“…In the United States, 192,370 new cases are estimated in 2009 with 40,170 women expected to die from this disease, representing a major health burden [2]. Apart from family history and genetic predisposition, there is substantial evidence that lifetime exposure to endogenous and exogenous estrogens plays a major role in developing breast cancer [3][4][5]. However, it is difficult to quantify lifetime estrogen exposure to identify individuals at risk for breast cancer.…”

Pharmacokinetics and tolerability of exemestane in combination with raloxifene in postmenopausal women with a history of breast cancer

“…It reduces the risk of vertebral fractures in postmenopausal women and is currently indicated for the prevention and treatment of osteoporosis [12]. Additionally, raloxifene reduces the incidence of invasive breast cancer in postmenopausal women with osteoporosis [13][14][15][16][17]. Unlike tamoxifen, raloxifene has little estrogenic effect on the endometrium [10] and may therefore serve as a safer alternative in the prevention setting.…”