Norman F Boyd

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..Future prospects for the application of PMD include mammographic screening, risk prediction in individuals, breast cancer prevention research, and clinical decision making...

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..We used MRI to measure the water content of the breast, which provides a measurement of the fibro-glandular content of breast tissue with similar accuracy to mammography, but without the attendant exposure to radiation...

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..This research was undertaken to determine whether the effect of hormone therapy on breast cancer risk is mediated by its effect on mammographic density...

..We have examined the associations of body size and mammographic density on breast cancer risk...

..Extensive mammographic density is associated with an increased risk of breast cancer and makes the detection of cancer by mammography difficult, but the influence of density on risk according to method of cancer detection is unknown...

..A better understanding of the factors that influence the response of breast tissue to these hormonal exposures may lead to an improved understanding of the aetiology of mammographic density and of breast cancer...

..We have assessed a novel method of assessing breast tissue that is fully automated, does not require an observer, and measures the volume, rather than the projected area, of the relevant tissues in digitized screen-film mammogram...

..We have examined the magnitude of the association of hormone exposure with PMD according to subsequent breast cancer risk...

..8 to 6.0 times that of women of the same age with little or no density. Menopausal status, weight, and parity account for 20 to 30 percent of the age-adjusted variation in the percentage of dense tissue...

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..This study does not support an association between IGF1 and these anthropometric measures. Study limitations, including sample size and capturing genetic variation at IGF1 with these markers, could mean associations were missed...

..Our findings suggest that the CYP17 A2 allele is associated with hormone levels, and interacts with insulin levels and diet to affect breast density levels and potentially breast cancer risk...

..14; 5'CA 18-20, P = 0.25; 5'CA >20, P = 0.20). The associations we found could be due to chance as many comparisons were made. Our results do not strongly support an association between these IGF1 variants and breast cancer risk...

..Cytochrome P450 1A2 (CYP1A2) is responsible for the metabolism of estrogens and many exogenous compounds, including caffeine...

..Menopause reduced density to a similar extent in the low-fat diet and control groups. If a low-fat diet reduces breast cancer risk, the effect is unlikely to be through changes in mammographic density at menopause...

..CONCLUSION: Percentage mammographic density in Singaporean Chinese women has similar associations with risk factors for breast cancer to those seen in Caucasians...

..Future work will examine whether these dietary differences are associated with biological markers of breast cancer risk...

..One enzyme that is able to affect both the mitogenic and mutagenic characteristics of estrogens is cytochrome P450 1A2 (CYP1A2), which is principally responsible for the metabolism of 17beta-estradiol...

..These findings indicate that COMT genotype is associated with several risk factors for breast cancer and suggest that the low-activity COMT*2 allele is associated with a reduced risk of breast cancer among premenopausal women...

..This study explores this relationship further by examining the influence of patterns of HRT use and the percentage of mammographic density on the detection of breast cancer by classification of interval cancer...

..The purpose of this study was to examine the extent to which mammographic density explains the association of family history of breast cancer with risk of the disease...

..Few studies have compared the prognostic value of tumor characteristics by type of breast cancer diagnosed in the interval between mammographic screenings with screen-detected breast cancers...

..The goal of this cross-sectional study was to examine breast cancer risk factors in populations with different risks for breast cancer...

..Therefore, we examined the association of IGF1 polymorphisms with circulating IGF-I levels and mammographic density...

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..Weight and carbohydrate intakes were associated with risk of ER-positive breast cancer...

..To examine this possible effect, we compared mammographic density in premenopausal women who had mammograms at different phases of the menstrual cycle...

..Mammographic breast density is a highly heritable (h2 > 0.6) and strong risk factor for breast cancer. We conducted a genome-wide linkage study to identify loci influencing mammographic breast density (MD)...

..Further research to examine the potential role of PMD as a mediator of the effects of other risk factors is required...

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..Later age at menopause is associated with a greater risk of breast cancer. Dietary factors may at least partially influence breast cancer risk through an effect on the age at menopause...

..62 (95% CI = 1.28-2.04). This meta-analysis indicates that a greater WHR is associated with increased risk of breast cancer and suggests that the avoidance of abdominal obesity may reduce risk of the disease...

..Clinical studies are ongoing to evaluate whether VBD can be a better indicator for breast cancer risk...

..Mouse models provide a powerful approach to the study of human diseases, but there is currently no model that is suited to the study of mammographic density...

..The use of a cancer registry approach is likely more representative of the population than clinic-based recruitment of families for genetic studies...

..The BCPCG analyzed potentially available clinical material from previous prospective studies and determined that a large case/control study to evaluate these new factors might be feasible at this time...

..Our previous twin study showed that the heritability of PMD was 63%. This study determined the heritabilities of the components of PMD, the areas of dense and nondense tissue in the mammogram...

..Subjects were randomized to 6 months of oral DFMO (0.5 g/m(2)/day) or placebo, followed by repeat fine-needle aspiration and biomarker assessment. The main study end point was an improvement in cytologic pattern...

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..Information about selected risk factors and anthropometric variables will be collected by telephone interview. Mammograms will be obtained and digitized, and the volume of the breast and of dense tissue determined. ..

..For these reasons it may be easier at early ages to detect genetic effects, as well as the effects of environmental exposures unique to early life. ..