Navigation Links
Delaying childbirth may reduce risk of an aggressive form of breast cancer
Date:12/12/2012

SEATTLE Younger women who wait at least 15 years after their first menstrual period to give birth to their first child may reduce their risk of an aggressive form of breast cancer by up to 60 percent, according to a Fred Hutchinson Cancer Research Center study. The findings, by Christopher I. Li, M.D., Ph.D., a member of the Public Health Sciences Division at Fred Hutch, are published online in Breast Cancer Research and Treatment.

"We found that the interval between menarche and age at first live birth is inversely associated with the risk of triple-negative breast cancer," Li said. While relatively uncommon, triple-negative breast cancer is a particularly aggressive subtype of the disease that does not depend on hormones such as estrogen to grow and spread. This type of cancer, which accounts for only 10 percent to 20 percent of all breast cancers, does not express the genes for estrogen receptor (ER), progesterone receptor (PR) or HER2/neu and therefore does not respond to hormone-blocking drugs such as Tamoxifen.

The study by Li and colleagues in the Public Health Sciences and Human Biology divisions at Fred Hutch is the first to look at how the interval between first menstrual period and age at first birth is related to the risk of this particular type of breast cancer. It is also the first study to look at the relationship between reproductive factors and breast cancer risk among premenopausal women, who have a higher risk of triple-negative and HER2-overexpressing breast cancer than postmenopausal women.

The study also confirmed several previous studies that have suggested that breast-feeding confers a protective effect against triple-negative disease. "Breast-feeding is emerging as a potentially strong protective factor against one of the most aggressive forms of breast cancer," Li said.

The mechanism by which breast-feeding and delaying childbirth reduces the risk of this form of breast cancer is unclear, Li said.

Previous research has shown, however, that the risk of the most common subtype of breast cancer, ER positive, is decreased among women who've had a full-term pregnancy and have breast-fed. The reason for this, researchers believe, is that the hormones of pregnancy induce certain changes in the cellular structure of the breast that seem to make the tissue less susceptible to this type of cancer.

The study has particular implications for African-American women, who experience disproportionately high rates of triple-negative disease. While the reason for this remains largely unknown, on a population level reproductive characteristics are known to vary by race, and compared to non-Hispanic white women, African-American women are more likely to start having children at a younger age and are less likely to breast-feed, Li said.

"Our observations that delayed childbearing and breast-feeding are protective against triple-negative breast cancer suggest that variations in reproductive histories by race may to some extent explain the higher rates of triple-negative disease in African-American women," Li said.

The study involved more than 1,960 Seattle-area women between the ages of 20 and 44, 1,021 with a history of breast cancer and 941 without. Reproductive histories among women without a history of breast cancer were compared to those of women with ER-positive (781), triple-negative (180) and HER2-overexpressing (60) breast cancer.

"This is an observational study and also one of the first to focus on premenopausal breast cancer and so our results require confirmation and thus should be interpreted with some caution," Li said.


'/>"/>

Contact: Kristen Woodward
kwoodwar@fhcrc.org
206-667-5095
Fred Hutchinson Cancer Research Center
Source:Eurekalert

Related medicine news :

1. Delaying radiation therapy after hysterectomy ups risk of uterine cancer recurrence
2. Delaying ADHD Meds Could Hurt Kids Math Scores
3. Vanderbilt study looks at benefits of progestogens to prevent early childbirth
4. Childbirth After 30 Lowers Risk of Endometrial Cancer: Study
5. Fear of Childbirth Linked to Longer Labor, Study Says
6. A promising clinical trial to reduce the severity of autistic disorders
7. Home visiting program for first-time moms may be struggling to reduce serious injuries to children
8. Weekly dose reduces targeted drugs side effects, but not its activity against ALL
9. Flaxseed Can Reduce Risk of Stroke by 50% According to New Study Reviewed by the Project for Natural Health Choices Inc.
10. Health-care practitioners must cooperate to reduce medication mismanagement, MU expert says
11. Caffeinated coffee may reduce the risk of oral cancers
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/24/2016)... ... June 24, 2016 , ... ... Sessions in Dallas that it will receive two significant new grants to support ... as PHA marked its 25th anniversary by recognizing patients, medical professionals and scientists ...
(Date:6/24/2016)... ... June 24, 2016 , ... Comfort Keepers® of San Diego, CA is ... Road To Recovery® program to drive cancer patients to and from their cancer treatments. ... the highest quality of life and ongoing independence. Getting to and from medical ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... Clinical Decision Making in Emergency Medicine conference in Ponte Vedra Beach, FL. The ... published in Emergency Medicine Practice and Pediatric Emergency Medicine Practice. , ...
(Date:6/24/2016)... ... June 24, 2016 , ... Strategic Capital Partners, LLC ... by obtaining investment capital for emerging technology companies. SCP has delivered investment ... resulted in more than a million dollars of capital investment for five companies. ...
(Date:6/24/2016)... ... June 24, 2016 , ... Today, MTI-GlobalStem, a ... cells and other difficult to transfect cells, announces its launch of the PluriQ™ ... Gene Editing System is a complete system for culturing and transfecting human ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016 Research and ... Global Market - Forecast to 2022" report to their ... treatment method for the patients with kidney failure, it replaces ... fluid from the patient,s blood and thus the treatment helps ... and chloride in balance. Increasing number of ...
(Date:6/23/2016)... Roche (SIX: RO, ROG; OTCQX: RHHBY) announced that it ... (procalcitonin) assay as a dedicated testing solution for people ... Roche is the first IVD company in the U.S ... assessment and management. PCT is a sepsis-specific ... blood can aid clinicians in assessing the risk of ...
(Date:6/23/2016)... WAYNE, Pa. , June 23, 2016 ... provider, will launch its next generation clinical outcomes platform, Bracket ... DIA Meeting held on June 26 – 30, 2016 in ... 6.0, the first electronic Clinical Outcome Assessment product of its ... DIA Booth #715. Bracket eCOA 6.0 is a ...
Breaking Medicine Technology: