PHILADELPHIA The combination of estrogen plus progestin, which women stopped taking in droves following the news that it may increase their risk of breast cancer, may decrease their risk of colorectal cancer, according to a report published in the January issue of Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research.
"Compared to women who had never taken these hormones, the use of estrogen plus progestin was associated with a reduced risk of colorectal cancer," said Jill R. Johnson, M.P.H., a doctoral student at the University of Minnesota School of Public Health.
The largest risk reduction, approximately 45 percent, was seen among women who had completed use of estrogen plus progestin five or more years previously.
Johnson and her colleagues extracted data from 56,733 postmenopausal women who participated in the Breast Cancer Detection Demonstration Project follow-up study. Hormone therapy use and other risk factors were ascertained through telephone interviews and mailed questionnaires between 1979 and 1998. During an average 15 years of follow-up, Johnson and colleagues identified 960 new cases of colorectal cancer in this population.
Any use of estrogen therapy was associated with a 17 percent reduced risk in colorectal cancer. Among those who used estrogen, the largest reductions were seen among those who were current users (25 percent reduced risk) and users of ten or more years duration (26 percent reduced risk).
Researchers also found a 22 percent reduced risk among those who had ever used estrogen plus progestin in combination. They further found a 36 percent reduction in risk among those who had used progestin sequentially or less than 15 days per month. Past users of estrogen plus progestin, who had stopped at least five years ago, had a 45 percent risk reduction.
Although Johnson's study was not designed to look at biological mecha
'/>"/>
| Contact: Jeremy Moore Jeremy.moore@aacr.org 267-646-0557 American Association for Cancer Research Source:Eurekalert |
Related biology news :
1. Food can affect a cell in the same way hormones do
2. Children distressed by family fighting have higher stress hormones
3. Apelin hormone injections powerfully lower blood sugar
4. Birth control has long-term effect on hormone exposure
5. Sex hormones link to heart risk
6. Plant steroids offer new paradigm for how hormones work
7. Prostate cancer vaccines more effective with hormone therapy
8. Growth hormones link to starvation may be clue to increasing life span, researchers find
9. High hormone levels in seabird chicks prepare them to kill their siblings
10. Scientists find potential protein biomarkers for growth hormone
11. Hunger hormone: Makes food more attractive
| Copyright © 2003-2012 Bio-Medicine. All rights reserved. ABOUT | CONTACT US | DISCLAIMER | PRIVACY POLICY | TERMS AND CONDITIONS |  |