Barbara Crossley

Influence of personal characteristics of individual women on sensitivity and specificity of mammography in the Million Women Study: cohort study

Abstract Objectives To examine how lifestyle, hormonal, and other factors influence the sensitivity and specificity of mammography. Methods Women recruited into the Million Women Study completed a questionnaire about various personal factors before routine mammographic screening. A sample of 122 355 women aged 50-64 years were followed for outcome of screening and incident breast cancer in the next 12 months. Sensitivity and specificity were calculated by using standard definitions, with adjustment for potential confounding factors. Results Breast cancer was diagnosed in 726 (0.6%) women, 629 in screen positive and 97 in screen negative women; 3885 (3.2%) were screen positive but had no subsequent diagnosis of breast cancer. Overall sensitivity was 86.6% and specificity was 96.8%. Three factors had an adverse effect on both measures: use of hormone replacement therapy (sensitivity: 83.0% (95% confidence interval 77.4% to 87.6%), 84.7% (73.9% to 91.6%), and 92.1% (87.6% to 95.0%); specificity: 96.8% (96.6% to 97.0%), 97.8% (97.5% to 98.0%), and 98.1% (98.0% to 98.2%), respectively, for current, past, and never use); previous breast surgery v no previous breast surgery (sensitivity: 83.5% (75.7% to 89.1%) v 89.4% (86.5% to 91.8%); specificity: 96.2% (95.8% to 96.5%) v 97.4% (97.3% to 97.5%), respectively); and body mass index < 25 v ≥ 25 (sensitivity: 85.7% (81.2% to 89.3%) v 91.0% (87.5% to 93.6%); specificity: 97.2% (97.0% to 97.3%) v 97.4% (97.3% to 97.6%), respectively). Neither sensitivity nor specificity varied significantly according to age, family history of breast cancer, parity, past oral contraceptive use, tubal ligation, physical activity, smoking, or alcohol consumption. Conclusions The efficiency, and possibly the effectiveness, of mammographic screening is lower in users of hormone replacement therapy, in women with previous breast surgery, and in thin women compared with other women.

Impact of use of hormone replacement therapy on false positive recall in the NHS breast screening programme: results from the million women study

About half of the women attending the NHS breast screening programme have used hormone replacement therapy.1 Although previous studies have reported that use of hormone replacement therapy increases the risk of being recalled after mammography for further assessment, with no subsequent diagnosis of breast cancer (“false positive recall”), the effect of different patterns of use is unclear.2 Relative risk of false positive recall in postmenopausal women in relation to time since last use of hormone replacement therapy. (Relative risk compared with never users (1057/44 427 recalled) stratified by screening centre, age, previous screening, body mass index, previous breast operation, and time since menopause in: current users of hormone replacement therapy (relative risk 1.64, 95% confidence interval 1.50 to 1.80; 1157/28 634 recalled); past users ceasing use <1 year ago (1.42, 1.08 to 1.86; 63/1758 recalled), 1-4 years ago (1.23, 1.04 to 1.46; 176/5910 recalled), and ≥5 years ago (1.07, 0.85 to 1.34; 92/3800 recalled)). Results are plotted according to the median number of years since last use of hormone replacement therapy in each of these categories From June 1996 to March 1998, 87 967 postmenopausal women aged 50-64 invited to routine …

Women doctors' use of hormone replacement therapy. High prevalence of use is not confined to doctors.

# High prevalence of use is not confined to doctors {#article-title-2} EDITOR,—A J Isaacs and colleagues report high rates of use of hormone replacement therapy among a sample of women doctors.1 They note the relative paucity of information regarding the prevalence of use and remark that this high rate among female doctors may “presage more widespread use in the general population.” We carried out a survey of use of hormone replacement …

Predictors of outcome of mammography in the National Health Service Breast Screening Programme.

BACKGROUND: Little is known about the factors influencing the risk of recall for assessment, invasive diagnostic procedures, and early rescreening after screening mammography. METHODS: From June 1996 to March 1998 women attending screening at 10 National Health Service Breast Screening Programme (NHSBSP) centres completed a self administered questionnaire and were followed up for their screening outcome. RESULTS: 1969 (3.3%) out of 60 443 women aged 50–64 who had never used hormone replacement therapy (HRT) were recalled for assessment but were not diagnosed with breast cancer (defined here as false positive recall). After adjustment for the variation between centres, false positive recall was decreased significantly among women who were likely to have had a previous NHSBSP mammogram (odds ratio (OR) 0.49, 95% confidence interval (95% CI) 0.38 to 0.63 for likely versus unlikely), who were postmenopausal (OR 0.65, 95% CI 0.56 to 0.76 for postmenopausal v premenopausal) and increased significantly for women reporting previous breast surgery (OR 1.64, 95% CI 1.42 to 1.89). Although false positive recall decreased significantly with parity and increasing body mass index, these effects were not large and no significant variation was found with age, education, family history of breast cancer, oral contraceptive use, sterilisation, exercise, smoking, or alcohol consumption. Altogether 655 (1.1%) women had an invasive diagnostic procedure; no personal characteristics were predictive of this outcome, 286(0.5%) were referred for early rescreening, and this was increased significantly by nulliparity and a family history of breast cancer. INTERPRETATION: Premenopausal women, those without a previous NHSBSP mammogram, and women with previous breast surgery have an increased risk of false positive recall by the NHSBSP.