Seattle, Washington 98101


The purpose of this study is to determine whether cessation of hormone replacement therapy for one or two months before a screening mammogram will improve its performance by decreasing breast density.

Study summary:

This randomized, controlled trial is designed to test whether short-term (1-2 months) HRT cessation will sufficiently lower breast density to decrease the proportion of women who receive a recommendation for additional evaluation following a screening mammogram, and to examine whether there is a trend by duration of cessation. The study is being conducted at Group Health Cooperative, a managed health care organization in western Washington State with an organized breast cancer screening program. We are recruiting 1,500 women and will randomize women to one of three HRT arms: 1) cessation two months before the screening mammogram; 2) cessation one month before; and 3) continued HRT use. We are using a computer-assisted method to measure mammographic breast density continuously. Mammography recall rates are being determined from an expert radiologist review of the mammograms, blinded to HRT status.


Inclusion Criteria: - 1 or more prior screening mammograms at Group Health Cooperative within the past 2 years - Currently taking HRT - Taking HRT at prior screening mammogram - Due for a screening mammogram Exclusion Criteria: - BI-RADS breast density of 1 (entirely fat) - Previous cardiovascular events (heart surgery, catheterization, stent bypass, angioplasty, stroke, DVT) - Previous breast cancer - History of breast implants - Breast reduction since last mammogram - Mastectomy - History of using Tamoxifen or Raloxifene - Declined contact or use of data for research



Primary Contact:

Principal Investigator
Diana SM Buist, Ph.D.
Group Health Cooperative

Dawn Fitzgibbons, MPH
Phone: 206-287-2380

Backup Contact:


Location Contact:

Seattle, Washington 98101
United States

Linda Palmer, RN
Phone: 206-287-2732

Site Status: Recruiting

Data Source:

Date Processed: June 25, 2018

Modifications to this listing: Only selected fields are shown, please use the link below to view all information about this clinical trial.

Click to view Full Listing

If you would like to be contacted by the clinical trial representative please fill out the form below.