Researchers say the number of breast cancers in the United States dropped sharply in 2003. The reduction follows a finding that links hormone replacement therapy to breast and other cancers in women. VOA's Jessica Berman reports.

An artist's rendering of a cancer tumor

In a special report published this week in the New England Journal of Medicine, a team of US researchers found the number of new breast cancer cases fell almost seven percent in 2003 from 2002 levels, and remained unchanged in 2004.

The drop means that 44,000 fewer cases of breast cancer were diagnosed in 2003 and again in 2004. Prior to this study, the American Cancer Society was reporting an estimated 300,000 new breast cancer diagnoses each year.

The driving force behind the decline emerged from a large study known as the Women's Health Initiative. The study involved 16,000 participants and looked at whether hormone replacement therapy prevents heart disease in post-menopausal women.

The hormone replacement therapy study was halted suddenly in 2002 when investigators found that the drugs promoted ovarian cancer. Millions of women stopped taking them.

Peter Ravdin is a cancer specialist at the M.D. Anderson Cancer Center in Houston, Texas and author of the paper in the New England Journal that noted the sharp drop in breast cancer diagnoses.

"You know, in retrospect, it is not surprising at all," said Peter Ravdin.

The results of the 2002 Women's Health Initiative showed that women past their child-bearing years, who were taking hormones for five or more years, had the highest cancer risk.

Ravdin says he is not surprised by that finding either.

"One of the things that always strikes me is this business about natural products," he said. "How can something natural be bad for you? You know, it is natural for a woman to have estrogen in her body? Well, it is. But maybe it is not that normal for her to have estrogen in her body when she is 60."

Meanwhile, in an article published in the British medical journal The Lancet, researchers following one million post-menopausal women for 15 years have reported an additional 1,000 deaths they suspect were a result of hormone replacement therapy.