Tamoxifen still not popular with women at risk of breast cancer

Apr 11 2005

Tamoxifen still not popular with women at risk of breast cancer a new study has revealed that less than one in five women eligible to take tamoxifen decided to take the drug after being told of its risks and benefits.

Of 255 women all over 50, with a high risk of developing breast cancer only 17.6 percent of the women decided to take the drug after interviews in which the risks and benefits of tamoxifen were discussed.

The interviews conducted by Joy Melnikow, M.D., M.P.H. of the University of California, Davis and her team included an evidence-based education session about tamoxifen and a follow-up evaluation of their knowledge about the drug and their decision to take or not take tamoxifen.

Understanding why women decide not to take tamoxifen even after education helps provide useful information when it comes to tailoring patient education to specific groups and for the development of new classes of cancer prevention drugs.

Tamoxifen is a synthetic estrogen receptor modulator, an effective breast cancer adjuvant therapy and it is also believed to help prevent breast cancer. A recent metanalysis of existing trials found a dramatic 38 percent reduction in the incidence of breast cancer in women who used tamoxifen which is also beneficial in reducing the risk of osteoporotic fractures. The public debate has been fuelled by the side effects which include an increased risk of endometrial cancer, pulmonary embolism, painful sexual intercourse, stroke, and cataracts.

The team found that the women in the study overestimated their breast cancer risk at ten times higher than it actually was, but despite that seven out of ten (70.9 percent) described their risk as low or average.

Among women who had heard of tamoxifen, few were inclined to try it, and very few changed their minds after the educational session. The decision on whether or not to use the drug was independent of the actual breast cancer risk and more about concerns to do with the adverse side-effects or low self-perceived breast cancer risk.

Women who were from low economic backgrounds or were confident about the benefits of Tamoxifen to reduce the breast cancer risk and prevent osteoporotic fractures were more disposed to use it.

Dr. Melnikow and colleagues concluded that the results of the study indicates that many high-risk women are unwilling to consider tamoxifen even with extensive education about its potential benefits and harms and that concerns over the drug's adverse effects were the primary reason for refusal.

The study will be published in the May 15, issue of CANCER, a peer-reviewed journal of the American Cancer Society.