Preliminary analysis and assessment of breast cancer risk in Japanese women.

e13092Background: No comprehensive breast cancer risk assessment model for Japanese women exists. Consequently, we have collected Japanese women’s data to investigate key BC risk factors with an objective of deriving a Japanese-women specific BC risk assessment model. Methods: We conducted a retrospective case-control study (paper-based with postal survey) at 15 institutions during 2014-2015. A survey was distributed to Japanese females aged 20-80 who had BC check-up. All pertinent data of a total of 34 factors including demographic and reproductive factors, social history and eating habits was collected. Cases and controls were divided into three groups respectively, premenopausal (PRE; 20 ≤ age < 45), perimenopausal (PERI; 45 ≤ age ≤ 55) and postmenopausal group (POST; 55 < age ≤ 80). Cases and control variables were compared by t-test, chi-square test and Wilcoxon rank sum test. Preliminary BC risk was calculated by logistic regression analysis. Results: A total of 3975 female Japanese datasets were co...