Featured Research

from universities, journals, and other organizations

New Clue To Racial Disparity In Breast Cancer Survival Rates

Date:
February 22, 2007
Source:
Children's Hospital Boston
Summary:
Why are African American women 1.5 to 2.2 times more likely than white women to die from breast cancer, despite their lower incidence of the disease? The reason may not be solely reduced access to medical care, researchers suggest in the International Journal of Surgery. They propose that the excess mortality occurs partly because black women are more likely to develop breast cancer before menopause, when surgery may be more apt to stimulate cancer growth.

Why are African American women 1.5 to 2.2 times more likely than white women to die from breast cancer, despite their lower incidence of the disease? Is it solely because they have less access to medical care? Maybe not, according to a new analysis that will appear in an upcoming issue of the International Journal of Surgery. In a paper now available online, researchers propose that the excess mortality occurs partly because black women are more likely than white women to develop breast cancer before menopause, when surgery to remove the tumor may pose a higher risk of stimulating cancer growth.

The researchers, led by Michael Retsky, PhD in the Vascular Biology Program at Children's Hospital Boston, note that African American women are diagnosed with breast cancer at an average age of 46, versus 57 for white women, and that their excess mortality first appeared in the mid-1970s, just when mammography for early detection was introduced. Early breast cancer detection leads to earlier surgical removals, which may actually spur relapse in some premenopausal cancer patients, the researchers say.

"Looking at what's happening in African American women provides a research opportunity to learn how to better screen for and treat premenopausal breast cancer overall," says Retsky. "There's much to learn that might translate into improved outcomes for all premenopausal women."

The analysis extends an earlier analysis published in 2005, which suggested that undergoing surgery before menopause may actually encourage early metastasis and relapse. That paper analyzed data from 1,173 women in Italy who had breast cancer surgery, and found that, among those with lymph node-positive cancer, 20 percent of premenopausal women relapsed within 10 months after surgery -- double the relapse rate in women diagnosed after menopause. The researchers suggested that these early relapses help explain the "mammography paradox" -- the puzzling observation that mammography screening in women aged 40 to 49 has significantly less benefit than in women aged 50 to 59.

The 2005 paper sparked a flurry of correspondence that led to the new analysis. One letter noted a commonly held belief in the African American community that "exposing a cancer to air" will cause it to spread, an idea often dismissed as superstition. Another letter, from Nigerian physician Isaac Gukas, MD, PhD, observed that over 70 percent of the breast cancer patients he saw in Africa were under age 45, and that they had a poor survival rate, often rapidly deteriorating after surgery. According to Gukas, it is common in Africa for women to seek alternative care before eventually presenting to a physician with locally advanced disease, for fear that treatment will "provoke" the cancer.

"These letters were compelling and impossible to ignore," says Retsky. "There may be some scientific basis for these folk sayings. We were unaware there was a racial difference in age of breast cancer diagnosis, and it has led us in a major new research direction." Gukas, now at the University of East Anglia (Norwich, UK), is a co-author on the current paper.

Although the researchers did not directly study the biological mechanisms of cancer relapse, they suggest that in women diagnosed before menopause, surgery is more likely to stimulate angiogenesis -- growth of new blood vessels -- which in turn spurs the growth of tiny, dormant metastases. They cite a large body of laboratory and animal data showing that primary tumors secrete angiogenesis inhibitors, and that surgical removal eliminates this inhibition and spurs the release of angiogenesis promoters in a wound-healing response. They also cite data showing hormonal differences between black and white women, which may influence angiogenesis and metastasis acceleration.

The researchers do not recommend any changes in screening or treatment protocols for breast cancer, feeling that more research is needed. They propose a number of ways to test their hypothesis:

  • By comparing blood vessel growth in primary versus recurrent tumors from black and white premenopausal and postmenopausal women;
  • By measuring angiogenesis inhibitors and promoters, before and after surgery, in premenopausal versus postmenopausal women and in black versus white women, and comparing these findings to cancer recurrence;
  • By conducting comparative genetic studies in black and white women to determine possible differences in activity of the genes that control angiogenesis.

"We do not have enough evidence to alter treatment schedules as of now," Gukas cautions. "However, if additional studies confirm our hypothesis, we may need to give these premenopausal women appropriate chemotherapy, including angiogenesis inhibitors, before surgery to ensure the best outcome."

Other co-authors were Romano Demicheli, MD, PhD, of the Istituto Nazionale Tumori (Milan, Italy) and William Hrushesky, MD, of the University of South Carolina.


Story Source:

The above story is based on materials provided by Children's Hospital Boston. Note: Materials may be edited for content and length.


Cite This Page:

Children's Hospital Boston. "New Clue To Racial Disparity In Breast Cancer Survival Rates." ScienceDaily. ScienceDaily, 22 February 2007. <www.sciencedaily.com/releases/2007/02/070221101400.htm>.
Children's Hospital Boston. (2007, February 22). New Clue To Racial Disparity In Breast Cancer Survival Rates. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2007/02/070221101400.htm
Children's Hospital Boston. "New Clue To Racial Disparity In Breast Cancer Survival Rates." ScienceDaily. www.sciencedaily.com/releases/2007/02/070221101400.htm (accessed September 30, 2014).

Share This



More Health & Medicine News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How 'Yes Means Yes' Defines Sexual Assault

How 'Yes Means Yes' Defines Sexual Assault

Newsy (Sep. 29, 2014) Aimed at reducing sexual assaults on college campuses, California has adopted a new law changing the standard of consent for sexual activity. Video provided by Newsy
Powered by NewsLook.com
Scientists May Have Found An Early Sign Of Pancreatic Cancer

Scientists May Have Found An Early Sign Of Pancreatic Cancer

Newsy (Sep. 29, 2014) Researchers looked at 1,500 blood samples and determined people who developed pancreatic cancer had more branched chain amino acids. Video provided by Newsy
Powered by NewsLook.com
Colo. Doctors See Cluster of Enterovirus Cases

Colo. Doctors See Cluster of Enterovirus Cases

AP (Sep. 29, 2014) Doctors at the Children's Hospital of Colorado say they have treated over 4,000 children with serious respiratory illnesses since August. Nine of the patients have shown distinct neurological symptoms, including limb weakness. (Sept. 29) Video provided by AP
Powered by NewsLook.com
Dr.'s Unsure of Cause of Fast-Spreading Virus

Dr.'s Unsure of Cause of Fast-Spreading Virus

AP (Sep. 29, 2014) Doctors at the Children's Hospital of Colorado say they have treated over 4,000 children with serious respiratory illnesses since August. Nine of the patients have shown distinct neurological symptoms, including limb weakness. (Sept. 29) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins