DAYTON, Ohio -- The benefits of estrogen replacement therapy
(ERT) in preventing heart disease generally outweigh the increased
breast cancer risk, says a cancer journal article that is the
second major research report in a month to associate increases in
breast cancer with post-menopausal ERT.
``We have calculated that, for each (new) case of breast cancer
in women due to long-term ERT use, more than six deaths from heart
disease are prevented,'' the University of Southern California
researchers writes in the Journal of the National Cancer Institute.
The report gives the most tangible risk-benefit analysis so far
of estrogen's role in raising breast cancer rates and lowering
heart disease rates, but the authors called for more research of
women with family histories of breast disease. ERT relieves
symptoms caused by menopause.
The USC researchers agreed with the Journal of the American
Medical Association report last month that the breast cancer rate
rises even more when estrogen is combined with progestin in order
to lower the risk of uterine cancer. They said taking the hormones
on alternate days is slightly riskier than taking both every day.
While JAMA placed the risk increases for breast cancer at 20
percent with estrogen alone and 40 percent with both hormones, the
JNCI report placed the percentage increases at 6 and 24,
respectively, after five years of hormone therapy. The JNCI report
said a woman's risk for breast cancer increases by 6 percent for
every five years she takes supplemental estrogen.
Women should consider their family histories and ``also be told
where uncertainty still exists in the risk-benefit equation,''
wrote the USC researchers, who studied more than 3,500 women.