THE EFFECT OF HORMONE REPLACEMENT THERAPY ON RECALL RATE IN THE NATIONAL-HEALTH-SERVICE BREAST SCREENING-PROGRAM

Purpose: Hormone replacement therapy (HRT) can lead to an increase in the density of breast parenchyma on mammography and to the development of mammographically visible cysts and fibroadenomas. These changes ma y obscure features indicative of benign processes or mimic those of a carcinoma on screening mammography. This study was designed to assess the effect of HRT usage on the recall rate of women attending for rout ine breast screening. Method: Details of HRT usage were taken from 569 9 consecutive women aged 49-64 attending for breast screening, Mammogr ams were read without knowledge of HRT usage and recall for assessment details collected. Results: A significant fall in recall rate was see n between the prevalent and incident screens in women not taking HRT ( P < 0.016). This fall was not present in women taking HRT. The recall rate for the incident screen of women on HRT was 37% higher than that for women who did not take HRT; however the positive predive value for cancer of recall was lower at 3.7% compared to 12.9%. Conclusion: The se results indicate that the recall rate for incident screening is lik ely to be higher in women on HRT. This increase in assessment will lea d to increased cost and anxiety in the screened population.