title: Does a short cessation of HRT decrease mammographic density?
abstract: BACKGROUND
  Hormone replacement therapy (HRT) is known to increase breast density, thus decreasing the sensitivity of cancer screening by mammography. Some authors recommend short cessation of HRT before mammography, but evidence showing the effect of such short cessation is limited. The purpose of this study is to examine whether a short cessation of HRT changes mammographic density.
  
  
  METHODS
  Forty-eight women taking HRT agreed to have mammograms taken before and after stopping HRT for 4 weeks. Mammographic density was measured by Wolfe's four-point classification, six-categorical visual scale and two different computer methods (interactive-thresholding and SMF). Density values of mammography before and after the cessation of HRT were compared using Wilcoxon signed-rank test for categorical variables and paired t-test for continuous variables. Changes in breast pain and tenderness during mammography, radiation dose, compression force, and breast thickness were also recorded.
  
  
  RESULTS
  No significant changes in mammographic density were observed by either visual or computer methods. There were no significant changes in breast pain or in tenderness on mammograms before and after the month's cessation of HRT. Radiographic measurements were not significantly altered by the 4-week cessation of HRT.
  
  
  CONCLUSIONS
  In this screening population, a 4-week cessation of HRT before mammograms did not significantly alter mammographic density.
authors.affiliation: Reproductive Healthcare, Dean Terrace Family Planning Clinic, Edinburgh, UK.
authors.forename: Kate
authors.initials: K
authors.lastname: Weaver
authors.forename: Masako
authors.initials: M
authors.lastname: Kataoka
authors.forename: Jean
authors.initials: J
authors.lastname: Murray
authors.forename: Berenice
authors.initials: B
authors.lastname: Muir
authors.forename: Elaine
authors.initials: E
authors.lastname: Anderson
authors.forename: Ruth
authors.initials: R
authors.lastname: Warren
authors.forename: Iqbal
authors.initials: I
authors.lastname: Warsi
authors.forename: Ralph
authors.initials: R
authors.lastname: Highnam
authors.forename: Anna
authors.initials: A
authors.lastname: Glasier
mesh_terms: D001940:Breast / Q000187:drug effects* / Q000473:pathology; D004334:Drug Administration Schedule; D015914:Estrogen Replacement Therapy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008327:Mammography; D008875:Middle Aged