Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Combination hormone therapy doubles breast density and quadruples risk of abnormal mammograms

19.10.2004


Postmenopausal women who take combination estrogen-plus-progestin hormone-replacement therapy for one year experience a twofold increase in breast density – a known risk factor for breast cancer – and a quadrupled risk of having an abnormal mammogram, according to new findings from a sub-study of the Women’s Health Initiative, or WHI.



Lead investigator Anne McTiernan, M.D., Ph.D., of Fred Hutchinson Cancer Research Center, presented these findings today at the third annual International Conference on Frontiers in Cancer Prevention Research hosted by the American Association for Cancer Research. "I was surprised by the magnitude of the effect – the doubling of breast density associated with combination-hormone therapy," said McTiernan, a member of Fred Hutchinson’s Public Health Sciences Division and lead physician of the WHI Clinical Coordinating Center, which is based at Fred Hutchinson.

The effect of HRT on breast density remained consistent throughout the two-year study period and was similar across ethnic and racial groups. The impact was particularly pronounced among women in the highest age bracket; those between 70 and 79 experienced a nearly threefold increase in breast density as compared to younger women, presumably because their breast tissue was less dense to begin with, McTiernan said. "These findings are unique in showing a sustained effect over two years and that even in older postmenpausal women breast density can increase in response to estrogen-plus-progestin therapy," McTiernan said.


The study involved a randomly selected subgroup of 413 racially and ethnically diverse postmenopausal women, ages 50 to 79, who were participants in the WHI estrogen plus progestin trial, which involved more than 16,500 women nationwide. Half of the women in the sub-study were randomly selected to receive estrogen plus progestin and half received an identical-looking placebo. All received a baseline mammogram at the beginning of the study and a follow-up mammogram after one or two years.

On average, participants were 62 years old and 12 years post-menopause at the beginning of the study. The majority of the women were non-Hispanic white (42 percent) or African-American (35 percent), 16 percent were Hispanic and 6 percent were Asian/Pacific Islander.

Breast density was measured by a computer-aided technique that calculated the amount of dense, or white-appearing, tissue on digitized mammography images. A woman’s risk of breast cancer and her chances of getting an accurate cancer diagnosis depend largely on the density of her breast tissue. Density is measured according to the ratio of connective and epithelial tissue, which appears on a mammogram as white; as compared to fatty tissue, which appears as black. Because cancer also appears as white on a mammogram, a high degree of breast density can make it difficult to spot tumors and other abnormalities.

In addition to being harder to image, dense breast tissue also appears to be more biologically active and susceptible to malignancy. Previous research at Fred Hutchinson has shown that women under 50 with predominantly dense breasts are four times more likely to develop breast cancer than those with little or no breast density. While density is determined largely by age and genetics, this study underscores the fact that other factors can play a part as well. In addition to hormone-replacement therapy, weight and physical activity also have been found to have an impact on breast density.

"By increasing breast density, the use of combination estrogen-plus-progestin hormone therapy may increase breast-cancer risk as well as decrease the sensitivity of screening mammography," McTiernan said. "Our results suggest that avoiding such hormone therapy may help improve the sensitivity of mammograms for detecting early breast cancers at a stage when they are most treatable."

In addition, McTiernan and colleagues suggest that health-care providers may want to track breast-density change during regular mammography screenings and use this information as part of the risk-benefit assessment when helping women choose whether to continue hormone therapy.

Warren Froelich | EurekAlert!
Further information:
http://www.aacr.org

More articles from Health and Medicine:

nachricht Hot cars can hit deadly temperatures in as little as one hour
24.05.2018 | Arizona State University

nachricht 3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>