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 Millions through license revenues
27.04.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

The TU Ilmenau develops tomorrow’s chip technology today

27.04.2017 | Information Technology

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

VideoLinks
B2B-VideoLinks
More VideoLinks >>>