PP01 International pooling project of mammographic density - insights of a marker of breast cancer risk from 22 diverse countries

摘要: Background Mammographic density (MD) is a strong intermediate risk factor for breast cancer (BC) and, having both genetic and environmental determinants, may account the over 6-fold international variations in BC incidence rates. The International Pooling Project of Density worldwide collaborative project MD targeting populations spanning range. aims are to (i) describe overall age-specific distributions MD, (ii) assess whether explained by individual-level determinants this marker (iii) examine correlate with corresponding Methods Each contributing study provided comparable data on factors mammographic images from random sample ˜ 400 general population women, who had undergone screening mammography. Images were transferred digitised screen-film, full-field or computed radiography digital DICOM format (raw processed). randomly allocated into batches reading using Cumulus 6 thresholding software, experienced readers blinded factors. Data pooled linked readings. Results calibrated according type image processed), adjusted type. 22 countries approximately 12,000 women included, age-standardised rates (ASR) 25.8 (India) 99 (The Netherlands) per 100,000 woman-years. To date, 9,635 participants have been (results will be updated). vary greatly across populations, example: mean age at menarche (in years) was 14.3 (95% CI 14.1–14.5) Korean 12.6 (12.5–12.8) Mexican women; parity 3.8 (3.6–4.1) Egyptian 1.3 (1.1–1.4) those Hong Kong; BMI kg/m 2 ) 33.7 (33.1–34.3) compared 22.3 (21.6–22.9) India. Differences these presented. Discussion perspective generated large exposure heterogeneity enabling wider investigation extent which an risk, within between populations.