Women who developed new-onset breast tenderness after starting estrogen plus progestin hormone replacement therapy were at significantly higher risk for developing breast cancer than women on the combination therapy who didn't experience such tenderness, according to a new UCLA study.
The research, published in the Oct. 12 issue of the Archives of Internal Medicine, is based on data from more than 16,000 participants in the Women's Health Initiative estrogen-plus- progestin clinical trial. This trial was abruptly halted in July 2002 when researchers found that healthy menopausal women on the combination therapy had an elevated risk for invasive breast cancer.
Researchers do not know why breast tenderness indicates increased cancer risk among women on the combination therapy, said the new study's lead researcher, Dr. Carolyn J. Crandall, a clinical professor of general internal medicine and health services research at the David Geffen School of Medicine at UCLA.
"Is it because the hormone therapy is causing breast-tissue cells to multiply more rapidly, which causes breast tenderness and at the same time indicates increased cancer risk? We need to figure out what makes certain women more susceptible to developing breast tenderness during hormone therapy than other women," Crandall said.
This study compared the daily use of oral conjugated equine estrogens (0.625 mg) plus medroxyprogesterone acetate (2.5 mg), or CEE+MPA, with the daily use of a placebo pill.
Of the participants in the trial, 8,506 took estrogen plus progestin and 8,102 were given placebos. Participants underwent mammography and clinical breast exams at the start of the trial and annually thereafter. Self-reported breast tenderness was assessed at the beginning of the trial and one year later, and invasive breast cancer over the next 5.6 years was confirmed by medical record review.
Women on the combination therapy who did not have breast tenderness at the trial's inception were found to have a threefold greater risk of developing tenderness at the one-year mark, compared with participants who were assigned placebos (36.1 percent vs. 11.8 percent). Among the women who did report breast tenderness at the beginning, the risk at one-year was about 1.26 times that of their counterparts on placebos.
Of the women who reported new-onset breast tenderness, 76.3 percent had been on the combination therapy.
Women in the combination therapy group who did not have breast tenderness at the outset but experienced new-onset tenderness at the first annual follow-up had a 48 percent higher risk of invasive breast cancer than their counterparts on combination therapy who did not have breast tenderness at the first-year follow-up.
"To our knowledge, no prior published studies have addressed whether there is an association between CEE+MPA–induced new-onset breast tenderness and breast cancer risk," Crandall said.
The study does have limitations. The data the researchers used assessed breast tenderness only annually and thus could have underestimated it. Also, the rates of women discontinuing the combination therapy and switching from placebos to active therapy were relatively high, though the researchers believe this could have decreased, rather than increased, the observed association between new-onset tenderness and cancer risk. And the results don't apply to other types of estrogen or progestin therapy.
Study co-authors were Rowan Chlebowski of UCLA; Aaron K. Aragaki, Anne McTiernan and Garnet Anderson of the Fred Hutchinson Cancer Research Center in Seattle; Susan L. Hendrix of Wayne State University–Hutzel Women's Hospital in Detroit; Barbara B. Cochrane of the University of Washington; and Lewis H. Kuller and Jane A. Cauley of the University of Pittsburgh.
Grants from the National Institute on Aging and the Tarlow-Eisner-Moss Research Endowment of the Iris Cantor–UCLA Women's Health Center funded Crandall's research. Funding for the Women's Health Initiative comes through the National Heart, Lung and Blood Institute of the National Institutes of Health.
The General Internal Medicine and Health Services Research Division in the department of medicine at the David Geffen School of Medicine at UCLA provides a unique interactive environment for collaborative efforts between health services researchers and clinical experts with experience in evidence-based work. The division's 100-plus clinicians and researchers are engaged in a wide variety of projects that examine issues related to access to care, quality of care, health measurement, physician education, clinical ethics and doctor-patient communication. Researchers in the division have close working relationships with economists, statisticians, social scientists and other specialists throughout UCLA and frequently collaborate with their counterparts at the RAND Corp. and the Charles Drew University of Medicine and Science.
For more news, visit the UCLA Newsroom or follow us on Twitter.
Enrique Rivero | EurekAlert!
Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT
Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine