A study from a research center in Seattle recently shows a drug which is known widely to cure breast cancer may lead to even severer symptoms, according to news reports on Wednesday.

Introduced in 1978, tamoxifen is used to prevent recurrences of cancer in women who have already undergone surgery to remove their tumors. However, a new research recently suggests it raises the risk of getting a more aggressive cancer in the healthy breast by more than four times.

"All treatments have risks and benefits," said Dr. Christopher Li, an associate member of the Fred Hutchinson Cancer Research Center in Seattle. "If you consider the full balance, for most women the benefits are going to far outweigh the risks."

The new study, which assessed the likelihood of developing a new cancer in the second breast, found that women who took tamoxifen for five years were 60 percent less likely than non-users to develop a new estrogen-sensitive tumor in the second breast, and 40 percent less likely to develop a new tumor of any kind in the second breast.

Several breast cancer experts said they are concerned that breast cancer patients who heard about the new study might stop taking their tamoxifen, even though the main reason to take the drug is to prevent the cancer they already have from recurring and spreading, which can lead to death.

Other experts agreed that the study is no reason to give up on tamoxifen. "The thing we have to remember is tamoxifen saves lives," said Dr. Victor Vogel, national vice president of research at the American Cancer Society.

(Agencies via Xinhua August 26, 2009)