In women who’ve been treated for breast cancer, use of the drug tamoxifen can help prevent recurrence of the disease. Now, new research indicates that the drug works equally well in black and white women.

The results also show that the risk of blood clots, a serious but uncommon side effect of the drug, is similar in both groups, according to the report in the Journal of the National Cancer Institute.

“There was no reason to think that the drug would behave differently in the two races, but we didn’t have the data to back it up,” lead author Dr. Worta McCaskill-Stevens, from the National Cancer Institute in Bethesda, Maryland, told AMN Health.

“The larger tamoxifen prevention trials that have been completed have had fewer minority women than we would have liked,” she added.

To compensate for this shortage, the researchers combined data from 13 trials, which included more than 20,000 women with breast cancer. Data from 8 of the trials were analyzed to assess tamoxifen’s cancer-preventing effects in black and white women, whereas data from all 13 trials were used to evaluate the risk of blood clots.

Tamoxifen reduced the risk of breast cancer by nearly the same amount in each race - about 25 percent.

Similarly, tamoxifen’s effect on blood clots did not vary significantly by ethnicity - women who used the drug were 2- to 3-times more likely to develop clots than nonusers. These risks were much higher if tamoxifen was given with chemotherapy, rather than alone.

“This study provides reassuring news,” McCaskill-Stevens said. “We hope this information will be useful to patients and physicians as they decide whether to use tamoxifen, which is now the only drug approved by the FDA for reducing the risk of breast cancer.”

SOURCE: Journal of the National Cancer Institute, December 1, 2004.