Short-Term Hormone Therapy Suspension and Mammography Recall

doi:10.1059/0003-4819-150-11-200906020-00003

Short-Term Hormone Therapy Suspension and Mammography Recall

A Randomized Trial

From Group Health Center for Health Studies, University of Washington, and Group Health Permanente, Seattle, Washington.

Abstract

Background: Without population-based evidence, some clinicians recommend short-term suspension of hormone therapy to improve the performance of mammography. Hormone therapy increases breast density, and abnormal screening mammograms are more common among women with denser breasts and among women using hormone therapy.

Objective: To test whether 1 to 2 months of hormone therapy suspension before screening mammography decreases additional mammographic imaging (recall) in women age 45 to 80 years.

Design: 3-group randomized, controlled trial.

Setting: Integrated health plan in western Washington from 2004 to 2007.

Patients: 1704 women age 45 to 80 years who used hormone therapy at their most recent screening (index) mammography, were due for screening (study) mammography, and were still using hormone therapy.

Intervention: Block random assignment (by breast density and hormone therapy type) to no hormone therapy suspension (n = 567) or suspension for 1 month (n = 570) or 2 months (n = 567) before study mammography. One blinded expert radiologist interpreted all mammograms.

Measurements: Recall was the primary outcome, and change in mammographic breast density (percentage and dense area) between the index and study mammograms was the secondary outcome.

Results: Mammography recall rates were 11.3% (61 of 542 women in the no-suspension group), 12.3% (50 of 478 women in the 1-month suspension group), and 9.8% (44 of 451 women in the 2-month suspension group). No subgroups were identified in which brief suspension of hormone therapy resulted in decreased mammography recall. With suspension, decreases in percentage of breast density were orderly and statistically significant: 0.1% (no-suspension group), −0.9% (1-month suspension group), and −1.5% (2-month suspension group). Similar ordered decreases were observed for dense area. Women in the suspension groups experienced increased menopause symptoms.

Limitations: Results can only be generalized to women age 45 to 80 years who have used hormone therapy for at least 1 year and will consider short-term suspension; most eligible women (61%) declined participation. Mammography recall was determined by 1 expert radiologist.

Conclusion: Brief hormone therapy suspension was associated with small changes in breast density and did not affect recall rates. No evidence supports short-term hormone therapy suspension before mammography.

Primary Funding Source: U.S. Department of Defense and the National Cancer Institute.

Article and Author Information

Note: The study team had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Acknowledgment: The authors thank Tammy Dodd, Linda Palmer, and Melissa Rabelhofer, as well as members of their advisory board: Hermien Watkins, Paula Hoffman, Deb Schiro, and Margrit Schubiger; members of the Data Safety and Monitoring Board: Susan Heckbert, Ben Anderson, Mary Anne Rossing, Robert D. Rosenberg, and Thomas Lumley; and Elizabeth Lin, the medical monitor. The authors also thank Robert Karl, Donna White, and Jo Ellen Callahan for their support for implementing this trial at Group Health. Finally, the authors thank Stephen Taplin, for his collaboration in getting this study funded when he was an investigator at Group Health Cooperative, and Rebecca Hughes for her editorial assistance.
Grant Support: The READ Trial was funded by the Department of Defense (DAMD17-03-1-0447). Study participants were recruited from the Group Health Breast Cancer Screening Program, which is funded by the National Cancer Institute (U01CA63731).
Potential Financial Conflicts of Interest: None disclosed.
Reproducible Research Statement: Study protocol: Available from Dr. Buist (e-mail, buist.d{at}ghc.org). Statistical code: Available from Ms. Anderson (e-mail, Anderson.Melissa{at}ghc.org). Data set: Not available.
Requests for Single Reprints: Diana S.M. Buist, PhD, MPH, Group Health Center for Health Studies, 1730 Minor Avenue, Suite 1600, Seattle, WA 98101-1448; e-mail, buist.d{at}ghc.org.
Current Author Addresses: Drs. Buist and Newton, Ms. Anderson, Ms. Aiello Bowles, Ms. Fitzgibbons, and Ms. Seger: Group Health Center for Health Studies, 1730 Minor Avenue, Suite 1600, Seattle, WA 98101-1448.
Dr. Reed: Obstetrics and Gynecology, Harborview Medical Center, Box 359865, Seattle, WA 98104-2499.
Dr. Gandara: Group Health Family Health Center, 125 16th Avenue East, Seattle, WA 98112.
Author Contributions: Conception and design: D.S.M. Buist, K.M. Newton.
Analysis and interpretation of the data: D.S.M. Buist, M.L. Anderson, S.D. Reed, E.J. Aiello Bowles, K.M. Newton.
Drafting of the article: D.S.M. Buist, M.L. Anderson, S.D. Reed, D. Seger.
Critical revision of the article for important intellectual content: D.S.M. Buist, M.L. Anderson, S.D. Reed, E.J. Aiello Bowles, K.M. Newton.
Final approval of the article: D.S.M. Buist, M.L. Anderson, S.D. Reed, E.J. Aiello Bowles, E.D. Fitzgibbons, J.C. Gandara, K.M. Newton.
Provision of study materials or patients: D.S.M. Buist, E.D. Fitzgibbons, J.C. Gandara.
Statistical expertise: D.S.M. Buist, M.L. Anderson.
Obtaining of funding: D.S.M. Buist.
Administrative, technical, or logistic support: D.S.M. Buist, E.D. Fitzgibbons, J.C. Gandara, D. Seger.
Collection and assembly of data: D.S.M. Buist, E.J. Aiello Bowles, E.D. Fitzgibbons, J.C. Gandara, D. Seger.
ClinicalTrials.gov registration number:NCT00117663.