Analysis of Circulating Biomarkers for Minimally Invasive Early Detection of Breast Cancer

A nested case–control study was conducted on plasma samples of 65 cases and 66 controls (discovery set) and 32 cases and 127 controls (validation set). 10 circulating microRNAs have been analyzed by RT-qPCR and 7 microRNA ratios (as the difference between their threshold cycles) have been included in a model to predict the presence of breast cancer. Together with the women identifier (andromeda_id) and the seven microRNA ratios, menopause staus (menopause), body mass index (bmi_di), the interaction term between menopause and BMI (bmi_men), the life-style score according to the World Cancer Research Fund (score_wcrf), the breast density classification (tabar), the cancer diagnosis (status) and the type of control (class2 - only for the validation cohort where there were two types of controls: mammography negatives (N) and mammography false-positives(N2)) are reported in the first sheet (validation set) and in the third sheet (discovery set). The second sheet contains the time intervals between enrollment with blood sampling and breast cancer diagnosis. This information was used only for the validation set, where these intervals were much higher than in the discovery set.

Raw threshold cycles (Ct) are available upon request.