Menopausal status and breast density
Author Block: C. Mckenna, S. Romanov, S. Rhodes, G. Evans, E. F. Harkness, S. M. Astley; Manchester/UK
Purpose: Increased breast density is a widely accepted risk factor for breast cancer. This study compares the density of premenopausal, perimenopausal and postmenopausal women using subjective, artificial intelligence and volumetric measurement methods.
Methods or Background: Data from 44,692 women in the UK PROCAS (Predicting Risk Of Cancer At Screening) study were analysed. Women self-identified as premenopausal (n=5,906), perimenopausal (n=8,687) and postmenopausal (n=30,099). Breast density was measured by one or more methods: subjective assessment recorded on Visual Analogue Scales (VAS), an AI method (MAI-VAS) trained to predict VAS on 'for processing' (raw) and 'for presentation' (processed) images and a volumetric method, Volpara (raw images only). Analysis of covariance (ANCOVA) was used to assess the relationship between breast density and menopausal status, adjusted for age, Body Mass Index, parity, Hormone Replacement Therapy use and alcohol consumption.
Results or Findings: In total, VAS scores were available for 39,411 women, MAI-VAS for 21,967 and Volpara for 35,378. For all methods of assessment, median breast density decreased as women progressed through the menopause. Median VAS scores were 33.5%, 27.3% and 22.0% for pre, peri and postmenopausal women respectively. Corresponding values were 34.0%, 29.6%, 23.5% for raw MAI-VAS; 34.7%, 29.5% and 23.8% for processed MAI-VAS and 6.9%, 5.7%, 4.8% for Volpara. ANCOVA analysis confirmed that the difference between groups remained, for all methods, after adjustment for other factors (p<0.001).
Conclusion: The decrease of breast density through the menopause can be demonstrated using a variety of measurement methods. Further analysis of longitudinal change in individual women will aid understanding of the implications for personalised screening.
Limitations: Limitations are the use of self-reported data and incomplete overlap of samples for each method.
Funding for this study: Prof Sue Astley and Prof D Gareth Evans are supported by the National Institute for Health and Care Research (NIHR) Manchester Biomedical Research Centre (BRC) (NIHR203308)
We would also like to thank the many radiographers in the screening programme and the PROCAS study staff for patient recruitment and data collection. PROCAS study was funded by the National Institute for Health Research (Reference Number RP-PG-0707-10031), with additional support from Prevent Breast Cancer. This abstract presents independent research; views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: Ethics approval for the study was through the North Manchester Research Ethics Committee (09/H1008/81).