Screening mammography: sensitivity and specificity in relation to hormone replacement therapy.

PURPOSE: To evaluate the possible effects of hormone replacement therapy (HRT) on the sensitivity and specificity of screening mammography. MATERIALS AND METHODS: Twenty thousand women aged 50 years or older were interviewed about use of HRT during the second round of screening mammography; of these, 3,126 were currently using, 2,158 had previously used, and 14,716 had never used HRT. Women with breasts known to be composed of predominantly fatty tissue were examined with one-view mammography; otherwise, two-view mammography was used. RESULTS: The sensitivity of screening mammography was 96% (95% confidence interval, 81.0%, 99.1%) in women currently using, 92% (61.5%, 99.8%) in women who had previously used, and 91% (85.7%, 96.8%) in women who had never used HRT. The specificity was 94% (93.3%, 95.0%), 95% (93.7%, 95.6%), and 95% (94.8%, 95.5%), respectively. There was a slight decrease in specificity with duration of treatment for the current-user group. However, specificity in women treated with continuous combined estradiol-progestin for less than 3 years (90%) was lower than that in women treated with other regimens (95%, P = .037). CONCLUSION: There was no decrease in the sensitivity of screening mammography in women currently using HRT, but there was a marginal decrease in specificity varying with the HRT regimen and duration of treatment.

Survival in breast cancer diagnosed between mammographic screening examinations.

In women drawn from a randomised, population-based trial of mammography screening for breast cancer the overall actuarial survival and disease-free survival for up to 7 years of observation were similar in 94 patients with interval cancers and 178 control patients with cancer diagnosed independent of screening. The similarity was confirmed by multiple regression analysis. These results contradict the hypothesis that a high growth rate of the primary tumour is associated with a greater metastatic potential and do not support the concept that patients with interval cancers should receive more aggressive local or systemic treatment.

Reduction in mortality from breast cancer after mass screening with mammography. Randomised trial from the Breast Cancer Screening Working Group of the Swedish National Board of Health and Welfare.

A randomised controlled trial to investigate the efficacy of mass screening with single-view mammography in reducing mortality from breast cancer was started in Sweden in 1977. 162 981 women aged 40 years or more and living in the counties of Kopparberg and Ostergötland were enrolled in the study and divided at random into 2 groups. Each woman in the study group was offered screening every 2 or 3 years depending on age. Women in the control group were not offered screening. This report is confined to the 134 867 women aged 40-74 years at date of entry. The results to the end of 1984 show a 31% reduction in mortality from breast cancer and a 25% reduction in the rate of stage II or more advanced breast cancers in the group invited to screening. 7 years after the start of the study the excess of stage I cancers in the study group largely outweighs the deficit of advanced cancers.