The effect of raloxifene on risk of breast cancer in postmenopausal women: Results from the MORE randomized trial

Steven R. Cummings, Stephen Eckert, Kathryn A. Krueger, Deborah Grady, Trevor J. Powles, Jane A. Cauley, Larry Norton, Thomas Nickelsen, Nina H. Bjarnason, Monica Morrow, Marc E. Lippman, Dennis Black, Joan E. Glusman, Alberto Costa, V. Craig Jordan

Research output: Contribution to journalArticle

1758 Scopus citations

Abstract

Context: Raloxifene hydrochloride is a selective estrogen receptor modulator that has antiestrogenic effects on breast and endometrial tissue and estrogenic effects on bone, lipid metabolism, and blood clotting. Objective: To determine whether women taking raloxifene have a lower risk of invasive breast cancer. Design and Setting: The Multiple Outcomes of Raloxifene Evaluation (MORE), a multicenter, randomized, double-blind trial, in which women taking raloxifene or placebo were followed up for a median of 40 months (SD, 3 years), from 1994 through 1998, at 180 clinical centers composed of community settings and medical practices in 25 countries, mainly in the United States and Europe. Participants: A total of 7705 postmenopausal women, younger than 81 (mean age, 66.5) years, with osteoporosis, defined by the presence of vertebral fractures or a fern' oral neck or spine T-score of at least 2.5 SDs below the mean for young healthy women. Almost all participants (96%) were white. Women who had a history of breast cancer or who were taking estrogen were excluded. Intervention: Raloxifene, 60 mg, 2 tablets daily; or raloxifene, 60 mg, 1 tablet daily and 1 placebo tablet; or 2 placebo tablets. Main Outcome Measures: New cases of breast cancer, confirmed by histopathology. Transvaginal ultrasonography was used to assess the endometrial effects of raloxifene in 1781 women. Deep vein thrombosis or pulmonary embolism were determined by chart review. Results: Thirteen cases of breast cancer were confirmed among the 5129 women assigned to raloxifene vs 27 among the 2576 women assigned to placebo (relative risk [RR], 0.24; 95% confidence interval [CI], 0.13-0.44; P < .001). To prevent 1 case of breast cancer, 126 women would need to be treated. Raloxifene decreased the risk of estrogen receptor-positive breast cancer by 90% (RR, 0.10; 95% CI, 0.04- 0.24), but not estrogen receptor-negative invasive breast cancer (RR, 0.88; 95% CI, 0.263.0). Raloxifene increased the risk of venous thromboembolic disease (RR, 3.1; 95% CI, 1.5-6.2), but did not increase the risk of endometrial cancer (RR, 0.8; 95% CI, 0.2-2.7). Conclusion: Among postmenopausal women with osteoporosis, the risk of invasive breast cancer was decreased by 76% during 3 years of treatment with raloxifene.

Original languageEnglish (US)
Pages (from-to)2189-2197
Number of pages9
JournalJournal of the American Medical Association
Volume281
Issue number23
DOIs
StatePublished - Jun 16 1999

ASJC Scopus subject areas

  • Medicine(all)

Fingerprint Dive into the research topics of 'The effect of raloxifene on risk of breast cancer in postmenopausal women: Results from the MORE randomized trial'. Together they form a unique fingerprint.

  • Cite this

    Cummings, S. R., Eckert, S., Krueger, K. A., Grady, D., Powles, T. J., Cauley, J. A., Norton, L., Nickelsen, T., Bjarnason, N. H., Morrow, M., Lippman, M. E., Black, D., Glusman, J. E., Costa, A., & Jordan, V. C. (1999). The effect of raloxifene on risk of breast cancer in postmenopausal women: Results from the MORE randomized trial. Journal of the American Medical Association, 281(23), 2189-2197. https://doi.org/10.1001/jama.281.23.2189