Navigation Links
New Analysis Says Evidence Lacking for HRT-Breast Cancer Link

By Kathleen Doheny
HealthDay Reporter

THURSDAY, March 14 ( HealthDay News) -- Although several large studies in recent years have linked the use of hormone therapy after menopause with an increased risk of breast cancer, the authors of a new analysis claim the evidence is too limited to confirm the connection.

Dr. Samuel Shapiro, of the University of Cape Town Medical School in South Africa, and his colleagues took another look at three large studies that investigated hormone therapy and its possible health risks -- the Collaborative Reanalysis, the Women's Health Initiative (WHI) and the Million Women Study.

Together, the results of these studies found overall an increased risk of breast cancer among women who used the combination form of hormone therapy with both estrogen and progesterone. Women who have had a hysterectomy and use estrogen-only therapy also have an increased risk, two of the studies found. The WHI, however, found that estrogen-only therapy may not increase breast cancer risk and may actually decrease it, although that has not been confirmed in other research.

After the WHI study was published in July 2002, women dropped hormone therapy in droves. Many experts pointed to that decline in hormone therapy use as the reason breast cancer rates were declining.

Not so, Shapiro said: "The decline in breast cancer incidence started three years before the fall in HRT use commenced, lasted for only one year after the HRT drop commenced, and then stopped."

For instance, he said, between 2002 and 2003, when large numbers of women were still using hormone therapy, the number of new breast cancer cases fell by nearly 7 percent.

In taking a look at the three studies again, Shapiro and his team reviewed whether the evidence satisfied criteria important to researchers, such as the strength of an association, taking into account other factors that could influence risk. Their conclusion: The evidence is not strong enough to say definitively that hormone therapy causes breast cancer.

The study is published in the current issue of the Journal of Family Planning and Reproductive Health Care.

The new conclusion drew mixed reactions from experts.

In an editorial accompanying the study, Nick Panay, a consultant gynecologist at the Queen Charlotte's & Chelsea Hospital in London, supported the conclusions of the new analysis. "If there is a risk, the risk is small, and the benefits of HRT can be life-altering," he wrote. "It is vital that we keep this in perspective when counseling our patients."

The hormone therapy in use today, Panay said, is lower in dose than those used in the previous research. "In principle, we tend to start with lower doses than we used to and increase as required until full symptom relief has been achieved," he said.

What is needed now, he said, is a clinical trial in which the hormone therapy in use today is compared with placebo, to evaluate the risks and benefits.

Another expert took a more middle-of-the-road view about the potential link.

"It would be hard to say the entire decline [in breast cancer rates] is due to the decline in HRT use," said Dr. Steven Narod, the Canada Research Chair in Breast Cancer at the University of Toronto.

According to Dr. Susan Gapstur, vice president of epidemiology for the American Cancer Society, the new analysis overlooks some other important information. "Indeed, there is a much larger body of scientific evidence from clinical trials and from observational epidemiologic studies comparing breast cancer incidence rates in women who used HRT to those who did not that demonstrate the risks and benefits of HRT for chronic diseases," she said.

"Women need to discuss with their doctors the risk and benefits of taking HRT for the primary prevention of chronic disease, including breast cancer," she added.

Narod said hormone replacement is an excellent therapy for some women. Therapy that includes progesterone carries more risk, he said, and limiting use to five years or less seems wise.

Shapiro has performed consulting work for the manufacturers of hormone therapy, and Panay has received grants from pharmaceutical companies.

More information

For more on hormone therapy after menopause, visit the American Cancer Society.

SOURCES: Samuel Shapiro, M.D., professor, public health and family medicine, University of Cape Town Medical School, South Africa; Susan Gapstur, M.P.H., Ph.D., vice president, epidemiology, American Cancer Society; Steven Narod, M.D., Ph.D., professor, public health sciences and nutritional sciences, Canada Research Chair in Breast Cancer, University of Toronto; Nick Panay, M.B.B.S., consultant gynecologist, Queen Charlotte's & Chelsea Hospital, London; March 14, 2013, Journal of Family Planning and Reproductive Health Care

Copyright©2012 ScoutNews,LLC.
All rights reserved  

Related medicine news :

1. Analysis of ASCOs QOPI® data finds significant improvement in performance on metrics for quality oncology care
2. Network analysis of the brain may explain features of autism
3. MinistryKeys: Using DISC Behavioral Analysis to Help Religious Organizations Achieve Goals for 2013
4. BRICS Mobility Aids and Transportation Equipment Market Analysis & 2018 Forecasts in New Research Report at
5. Rice University analysis links ozone levels, cardiac arrest
6. Deep genomic analysis identifies a micro RNA opponent for ovarian cancer
7. CT texture analysis of tumors may be a valuable biomarker in localized esophageal cancer
8. Re-Analysis Refutes Diet Guidelines Favoring Vegetable Fats
9. Economic analysis finds penicillin, not "the pill," may have launched the sexual revolution
10. Canada In Vitro Diagnostics Market Analysis and Forecasts to 2017 in New Research Report at
11. U.S. Medical Waste Market Analysis: Treatment, Containment, Management and Disposal Products Reviewed in New Research Report at
Post Your Comments:
Related Image:
New Analysis Says Evidence Lacking for HRT-Breast Cancer Link
(Date:11/27/2015)... ... November 27, 2015 , ... According to an article ... Dental Association meeting in Washington D.C. revolved around the fact that proper dental care, ... The talk stressed the link between periodontal disease (more commonly referred to as gum ...
(Date:11/27/2015)... ... November 27, 2015 , ... ... and convenient way to dispense prescription medications at home, so he invented the ... to monitor and dispense prescription medications. In doing so, it could help to ...
(Date:11/27/2015)... ... November 27, 2015 , ... MPWH, the No.1 Herpes-only dating community in the world, revealed that ... ). More than 3.7 billion people under the age of 50 – or 67% ... WHO's first global estimates of HSV-1 infection . , "The data shocks us highly!" ...
(Date:11/27/2015)... ... 2015 , ... Keeping in mind challenges faced by parents ... consultation, has collaborated with a leading web-based marketplace for extra-curricular activities for children ... and bring advice from parenting experts within their reach. As a part of ...
(Date:11/27/2015)... ... ... Indosoft Inc., developer and distributor of the world-class Asterisk ... Term Support) into its Q-Suite 5.10 product line. , Making the change to ... of Asterisk that will receive not only security fixes, but feature and bug ...
Breaking Medicine News(10 mins):
(Date:11/25/2015)... WASHINGTON , Nov. 25, 2015  The ... Obstetricians and Gynecologists (ACOG), and the March of ... bipartisan Protecting Our Infants Act of 2015 ... the number of newborns born exposed to drugs, ... Since the bill,s introduction, all three organizations have ...
(Date:11/25/2015)... Nov. 25, 2015 On Tuesday, November ... bellwether trial against Wright Medical Technology, Inc. for ... Conserve metal-on-metal hip implant device, awarded $11 million ... two week trial and three days of deliberations, ... device was defectively designed and unreasonably dangerous, and ...
(Date:11/25/2015)... Israel , November 25, 2015 ... KTOV ) (TASE: KTOV), a biopharmaceutical company focused ... treatment of various clinical conditions, today announced the closing ... American Depository Shares ( ADSs ), each representing 20 ... up to 3,158,900 ADSs. The ADSs and warrants were ...
Breaking Medicine Technology: