Breast Cancer Prevention Drug Underused
Women With Abnormal Biopsies Most Likely to Take Tamoxifen
March 22, 2004 -- Women at high risk for breast cancer can reduce their chances of getting the disease by taking the drug tamoxifen, but it appears that only a small fraction of those who are eligible are doing so.
Although tamoxifen has been shown to reduce the risk of breast cancer in high-risk women by as much as 50%, new research shows that doctors are still reluctant to prescribe it and many women aren't willing to take it.
"Our findings indicate that both physician practice and the attitudes of at-risk women are responsible for the low rates of tamoxifen usage," says researcher Monica Morrow, MD.
Millions of Women Could Benefit
Used for almost three decades to treat women with advanced or metastatic breast cancer, tamoxifen was approved in 1998 to help prevent breast cancer in healthy women at high risk for the disease.
An earlier study indicated that as many as 10 million women in the U.S., or 15% of the adult female population, are considered high risk and are candidates for its use. While it is not clear how many women are taking the drug for breast cancer prevention, the researchers suspect it's likely a very small percentage of those who are eligible.
In the newly published study, researchers followed 219 women at increased risk for breast cancer being evaluated at Northwestern Memorial Hospital in Chicago. The researchers tried to identify what factors were important to both doctors and high-risk women in making a decision regarding the use of tamoxifen.
The women were deemed to be at high risk for breast cancer based on several factors, including:
- Age (the older the woman, the higher the risk)
- Family history
- Having their first child later in life (later first pregnancy increases breast cancer risk)
- History of abnormal breast biopsy
These factors were then used to calculate a score to indicate breast cancer risk, which determined eligibility for preventive treatment with tamoxifen.
Overall, only 63% of the women were offered tamoxifen and 43% of those women agreed to take the drug.
The investigators reported that the drug tended to be offered most to women at the highest risk for breast cancer.
Women who had had a breast biopsy showing abnormal breast cells -- either precancerous cells called atypical hyperplasia or very early breast cancer known as lobular carcinoma in situ -- were far more likely to be offered tamoxifen. In addition, these women were far more likely to take tamoxifen -- 70% agreed to take the drug. The findings are published in the latest online edition of the journal Cancer.
"It is not surprising that women who had biopsies indicating that something might be wrong would be the ones who were most willing to take tamoxifen," American Cancer Society deputy chief medical officer Len Lichtenfeld, MD, tells WebMD. "Other risk factors like starting your period early or having children late, or even having a family history of breast cancer, may not seem as real." HRT Experience