Breast density is a strong intermediate endpoint to investigate the association between early-life exposures and breast cancer risk. This study investigates the association between early-life growth and breast density in young adult women measured using Optical Breast Spectroscopy (OBS) and Dual X-ray Absorptiometry (DXA). OBS measurements were obtained for 536 female Raine Cohort Study participants at ages 27–28, with 268 completing DXA measurements. Participants with three or more height and weight measurements from ages 8 to 22 were used to generate linear growth curves for height, weight and body mass index (BMI) using SITAR modelling. Three growth parameters (size, velocity and timing) were examined for association with breast density measures, adjusting for potential confounders. Women who reached their peak height rapidly (velocity) and later in adolescence (timing) had lower OBS-breast density. Overall, women who were taller (size) had higher OBS-breast density. For weight, women who grew quickly (velocity) and later in adolescence (timing) had higher absolute DXA-breast density. Overall, weight (size) was also inversely associated with absolute DXA-breast density, as was BMI. These findings provide new evidence that adolescent growth is associated with breast density measures in young adult women, suggesting potential mediation pathways for breast cancer risk in later life.
乳腺密度是研究生命早期暴露因素与乳腺癌风险关联的重要中间终点。本研究通过光学乳腺光谱法（OBS）和双能X线吸收法（DXA）测量年轻成年女性的乳腺密度，探讨生命早期生长情况与乳腺密度之间的关联。研究对536名27-28岁的雷恩队列研究女性参与者进行了OBS测量，其中268人完成了DXA测量。选取8至22岁期间拥有三次及以上身高体重测量数据的参与者，采用SITAR模型构建身高、体重和体质指数（BMI）的线性生长曲线。在调整潜在混杂因素后，分析了三种生长参数（体型、速度、时相）与乳腺密度指标的关联。研究发现：青春期身高增长较快（速度参数）且生长突增期较晚（时相参数）的女性，其OBS测得的乳腺密度较低；总体而言，身高较高（体型参数）的女性OBS乳腺密度较高。体重方面：青春期增长较快（速度参数）且增重高峰较晚（时相参数）的女性，其DXA测得的绝对乳腺密度较高；而总体体重（体型参数）及BMI均与绝对乳腺密度呈负相关。这些发现为青春期生长状况与年轻成年女性乳腺密度存在关联提供了新证据，提示其可能构成影响未来乳腺癌风险的潜在中介路径。
The Prospective Association between Early Life Growth and Breast Density in Young Adult Women
肿瘤(癌症)患者之家