Hormone Therapy Reduces Colon Cancer Risk
Reported January 08, 2009
(Ivanhoe Newswire) — Recent news that hormone therapy may increase the risk of breast cancer had many women concerned about taking estrogen plus progestin, but new research shows those same hormones may decrease their risk of developing colorectal cancer.
“Compared to women who had never taken these hormones, the use of estrogen plus progestin was associated with a reduced risk of colorectal cancer,” Jill R. Johnson, M.P.H., a doctoral student at the University of Minnesota School of Public Health, was quoted as saying.
Johnson and her colleagues studied data collected from 56,733 postmenopausal women. Among women who had completed use of estrogen plus progestin five or more years previously there was a 45 percent risk reduction of developing colorectal cancer compared to women who had never taken the hormones. Women who were currently taking estrogen had a 25 percent reduced risk and women who had been taking estrogen for more than 10 years had a 26 percent reduced risk. They also found a 36 percent reduction in risk among those who had used progestin sequentially or less than 15 days per month.
Although the study did not look into biological reasons for the protective effects, previous research suggests the hormones may play a role in reducing insulin-like growth factors, which could explain the risk reduction.
SOURCE: Cancer Epidemiology, Biomarkers and Prevention, 2009;18:196-203