Association of Body Size Measurements and Mammographic Density in Korean Women: The Healthy Twin Study

Abstract

Background: Both greater body size and higher mammographic density seem to be associated with a risk of breast cancer. To understand a mechanism through which body size confers a higher risk of breast cancer, associations between mammographic measures and various measures of body size were examined.Method: Study subjects were 730 Korean women selected from the Healthy Twin study. Body size measurements were completed according to standard protocol. Mammographic density was measured from digital mammograms using a computer-assisted method from which the total area and the dense area of the breast were calculated, and nondense area and percent of dense area were straightforwardly derived. Linear mixed models considering familial correlations were used for analyses.Results: Total and nondense areas were positively associated with current body mass index (BMI), BMI at 35 years, total fat percent, waist circumference, and waist-hip ratio, whereas percent dense area was inversely associated with these characteristics in both premenopausal and postmenopausal women. Height was not associated with any mammographic measure. Total and nondense areas had strong positive genetic correlations with current BMI, total fat percent, waist circumference, and waist-hip ratio, whereas percent dense area had strong inverse genetic correlations with these body size measurements.Conclusion: Mammographic density and obesity are inversely associated with each other possibly from common genetic influences that have opposite effects on mammographic density and obesity in Korean women.Impact: The association between obesity and breast cancer does not seem to be mediated through mammographic density. Cancer Epidemiol Biomarkers Prev; 19(6); 1523-31. ©2010 AACR.

Anthropometric factors, adult weight gain, and mammographic features

“…The negative association we observed between anthropometric factors and percent density or dense area is consistent with the literature [21][22][23][24][25][26][27][28][29][30], although more conflicting results are reported for dense area [21,[24][25][26][27][28][29][30], possibly due to important variation in the adjustments performed in the analyses. Interestingly, this inconsistency is also illustrated in our results by the inversion of the correlations between adiposity and dense area after adjustment for non-dense area.…”

“…BMI, waist circumference, or WHR has been shown to be negatively associated with percent density [21][22][23][24][25][26][27][28][29][30] or absolute dense area [24-26, 29, 30], although not consistently for the latter [21,27,28], while positively associated with absolute non-dense area [21,[24][25][26][27][28][29][30]. Meanwhile, the association between weight gain during adulthood and breast density was seldom studied and led to inconsistent results [21][22][23].…”

Given breast cancer, does breast size matter? Data from a prospective breast cancer cohort

“…Investigating fat/gland ratio or mammographic density in this group of women may be of value (27), but has not been part of this study. All body measurements were obtained by trained nurses prior to surgery and subsequent events, minimizing the risk for bias.…”

“…Even though breast size is strongly correlated with BMI (27), only one third of the genes contributing to breast size has been shown to influence BMI (28). Larger breast size was associated with higher IGF-1 levels in young nulliparous women not using oral contraceptives (29).…”

Investigating the Factors Affecting the Mammographic Density of Breast Tissue in Patients Referred to the Breast Cancer Research Center, Iran

“…Breast tissue density is the strongest factor in the increased risk of breast cancer and various studies have indicated that women with a high density of breast tissue are 4-6 times in higher risk of breast cancer than women with low breast tissue density [5,[7][8][9][10][11][12][13]. In total, in different studies, various factors such as age, hormones usage, factors associated with parents, body mass index (BMI) and reproductive factors have been considered effective on breast tissue density, but no definitive cause for this issue is known yet [8][9][10][11][12][13][14]. Given that the increased density of breast tissue can lead to increased risk of breast cancer, using intervention strategies for reducing its density will be very important.…”