HRT ups breast cancer risk across racial groups
|
|
The use of estrogen-progestin hormonal therapy increases the risk of breast cancer among postmenopausal women regardless of racial differences, according to results of a study of more than 55,000 American women of different racial and ethnic backgrounds reported in the International Journal of Cancer September 16th.
“The most important finding in this paper,” said Dr. Malcolm Pike of the University of Southern California in Los Angeles, “is that the increased risk of breast cancer from menopausal estrogen/progestin replacement therapy is found in all ethnic groups we studied—African Americans, Hawaiians, Japanese Americans and Latinas (mainly Mexican-Americans) as well as in whites.”
“The result in whites confirms earlier reports,” he noted.
Millions of women have relied on hormone replacement therapy for many years, but recent research has suggested that the benefits of the treatment—alleviating hot flashes, mood swings and other bothersome symptoms of the menopause and preventing osteoporosis—may be outweighed by its risks, specifically, breast cancer, heart attack and strokes.
Most previous studies that have shown a link between menopausal hormone therapy and increased breast cancer risk have been conducted in white women and few have considered prognostic factors such as weight (body mass index). The current study provides some of the first results comparing breast cancer risk among different racial and ethnic groups in relation to hormone therapy use.
Among the 55,000+ women in the study, 1615 cases of breast cancer were diagnosed over an average of 7.3 years.
Current users of estrogen-progestin therapy had a 29 percent higher risk of developing breast cancer after 5 years of treatment, while users of estrogen-only therapy had only a 10 percent increased risk.
The increase in breast cancer risk with combined estrogen-progestin therapy was seen in all five ethnic groups and the increase with estrogen-only therapy was seen in four of the five groups.
The data also hint that the risk of breast cancer for estrogen-progestin users is somewhat higher for lean women—those with a body mass index below 25—compared with heavier women. The authors emphasize, however, “data on this aspect of the relationship between hormone therapy use and risk are scarce and it is too early to draw a firm conclusion.”
They also note there was “still a clear increase in risk in heavier women.”
Summing up, Pike noted that “menopausal estrogen-alone therapy is much safer as regards breast cancer, but can only be used for a short time without increasing a woman’s risk of endometrial cancer.”
“A proposed solution to this dilemma,” he offered, “is to still add some progestin to the estrogen replacement therapy but to add it much less frequently than monthly or to use an intrauterine device that contains a progestin, but that effectively provides progestin only to the uterus.”
SOURCE: International Journal of Cancer September 16, 2005.
Print Version
Tell-a-Friend comments powered by Disqus
