Preferences of Women Evaluating Risks of Tamoxifen (POWER) study of preferences for tamoxifen for breast cancer risk reduction

Cancer. 2005 May 15;103(10):1996-2005. doi: 10.1002/cncr.20981.


Background: The objective of this study was to understand the attitudes and preferences of risk-eligible women regarding use of tamoxifen for breast cancer risk reduction.

Methods: A cross-sectional, mixed-methods interview study was conducted at a university medical center and at community sites. Participants were women who had an estimated 5-year breast cancer risk > or = 1.7% and no prior breast cancer. Interviews were conducted in English or Spanish. The interview included a 15-minute, standardized educational session on the potential benefits and harms of tamoxifen followed by close-ended and open-ended questions about participants' inclinations to take tamoxifen and factors important to their decision. A demographic questionnaire, a test on knowledge of potential benefits and harms of tamoxifen, and an interview evaluation were included.

Results: Two hundred fifty-five women completed interviews. Their estimated mean 5-year breast cancer risk was 2.8%; and their mean self-perceived 5-year risk was 32.7%. After the educational intervention, 45 women (17.6%) were inclined to take tamoxifen. Very high risk women (> 3.5%) were no more inclined to take it than women with lower risk (1.7-3.5%). In a multivariable analysis, lower income, confidence in the effectiveness of tamoxifen, and concern about fractures were associated with being inclined to take it; concern about pulmonary embolism, dyspareunia, cataracts, and low self-perceived breast cancer risk were associated negatively with taking tamoxifen. Participants expressed concerns about adverse effects.

Conclusions: Less than 20% of women were interested in tamoxifen after education about potential benefits and harms, despite a very high self-perceived breast cancer risk. Candidate chemoprevention agents must have few potential adverse effects to achieve widespread acceptance.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Anticarcinogenic Agents / adverse effects
  • Anticarcinogenic Agents / therapeutic use*
  • Attitude to Health*
  • Breast Neoplasms / prevention & control*
  • Cataract / chemically induced
  • Chemoprevention
  • Cross-Sectional Studies
  • Decision Making
  • Dyspareunia / chemically induced
  • Female
  • Fractures, Bone / chemically induced
  • Health Knowledge, Attitudes, Practice
  • Humans
  • Income
  • Middle Aged
  • Patient Education as Topic
  • Patient Satisfaction*
  • Pulmonary Embolism / chemically induced
  • Risk Assessment
  • Risk Factors
  • Tamoxifen / adverse effects
  • Tamoxifen / therapeutic use*


  • Anticarcinogenic Agents
  • Tamoxifen