25-10-2012, 10:26 AM
A Population-Based Randomized Trial to Assess the Effects of Short-Term Cessation of HRT on Mammography Assessments and Breast Density
ABSTRACT
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 will be conducted at
Group Health Cooperative, a managed health care organization with an organized breast cancer screening program. WE will
use automated to identify HRT users who are due for screening mammograms. Women will be recruited through mailed
correspondence and telephone contact. A total of 1500 women will be recruited and randomized to one of three HRT arms:
1) cessation two months before the screening mammogram, 2) cessation one month before, and 3) continued HRT use. Breast
density will be measured using a computer assisted method and recall rates will be determined from an expert radiologist
review of the mammograms, blinded to HRT status. We will test whether: 1) HRT cessation I or 2 months before a screening
mammogram reduces the likelihood of receiving a recommendation for additional evaluation compared to women who
continue using HRT; 2) HRT cessation for I versus 2 months affects the likelihood of receiving a recommendation for
additional evaluation; and 3) there is a greater change in breast density (to lower breast density) among women who stop HRT
I or 2 months before a screening mammogram to those who do not stop HRT. Change in breast density will be measured as
the difference between breast density on the screening mammogram before the trial (while on HRT) and during the trial.