Association between Breast Density and Breast Cancer Risk factors：A cross-sectional study in Taiwan

• Main Authors: Lu, Hsin-ying, 盧心瑩
• Other Authors: Chou, Yu-ching
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/41771931466191983343

碩士 === 國防醫學院 === 公共衛生學研究所 === 100 === There have been several studies investigating correlation between breast cancer risk factors and breast density but most of their subjects are Western women, with very few Asians included. Moreover, measurement of breast density is determined by doctors' subjective interpretation or only by two-dimensional mammographic images. In this study, a physical model of X-ray imaging on Quantra software adopted (different attenuation coefficients of breast tissues and photoanode materials, kVp, mAs, etc) can calculate the volume of glandular tissues and adipose tissues in breasts. This measurement has high validity and is repeatable. It is discovered in the results of this study that in a multivariate regression model, age, body mass index, menstrual status and times of pregnancy are negatively correlated with breast density percentage (volume) while places of residence, hormones and personal medical history are positively correlated (p<0.05). Besides body mass index, correlation between breast cancer risk factors and breast density percentage (volume) is consistent with that between breast cancer risk factors and breast glandular tissues. Breast cancer risk factors have 16.1% explanatory power on breast density (volume) and 20.5% on glandular tissue volume but it is considered in this study that glandular tissues in breasts are more suitable to predict breast cancer risk. Although this study is a cross-sectional research without causal timing, according to correlation between some breast cancer risk factors and breast glandular tissues, it can be inferred that glandular tissues within breasts may be the mediator for some breast cancer risk factors that affect breast cancer susceptibility. If this hypothesis is verified by future longitudinal research methodology, the indicator of breast glandular tissues will increase the predictive accuracy of breast cancer risk. It is also discovered in the result of this study that breast density indeed has influence on doctors' interpretation.