Longitudinal Trends in Mammographic Percent Density and Breast Cancer Risk

Abstract

Background: Mammographic density is a strong risk factor for breast cancer. However, whether changes in mammographic density are associated with risk remains unclear. Materials and Methods: A study of 372 incident breast cancer cases and 713 matched controls was conducted within the Mayo Clinic mammography screening practice. Controls were matched on age, exam date, residence, menopause, interval between, and number of mammograms. All serial craniocaudal mammograms 10 years before ascertainment were digitized, and quantitative measures of percent density (PD) were estimated using a thresholding method. Data on potential confounders were abstracted from medical records. Logistic regression models with generalized estimating equations were used to evaluate the interactions among PD at earliest mammogram, time from earliest to each serial mammogram, and absolute change in PD between the earliest and subsequent mammograms. Analyses were done separately for PD measures from the ipsilateral and contralateral breast and also by use of hormone therapy (HT). Results: Subjects had an average of five mammograms available, were primarily postmenopausal (83%), and

Mammographic density, lobular involution, and risk of breast cancer

“…Two longitudinal studies have examined the relationship between change in density and breast cancer risk, one over an average of 4 -5 years (Maskarinec et al, 2006) and the other over an average of 7 years (Vachon et al, 2007a). Both used computer-assisted quantitative measurement of mammographic density and both showed that change in density with time was similar in women who developed breast cancer and those who remained free of disease (an example is shown in Figure 1B), but that at all ages, density was more extensive in women who develop breast cancer.…”

“…With the exception of the study of Kerlikowske, the available evidence suggests that it is the extent of density at a given age, rather than the rate of change of density with increasing age, that is related to breast cancer risk (Maskarinec et al, 2006;Vachon et al, 2007a). However, there are important gaps in knowledge concerning cumulative exposure.…”

“…Vachon et al (2007a) recently drew attention to similarities between age-related breast involution and mammographic density.…”

Imperfect Correlation of Mammographic and Clinical Breast Tissue Density

“…In the former situation, clinical breast exam may find tumors which are not detected in mammography (Drukteinis et al, 2013). Moreover, high density breasts in mammography are at a higher risk for breast cancer (McCormack and dos Santos Silva, 2006;Vachon et al, 2007;Heine et al, 2008;Zulfiqar et al, 2011;Phipps et al, 2012). When using breast density as a predictor of breast cancer risk, the majority of the studies report 2-to 6-fold increased risks for the highest group in comparison with the lowest risk categories (McCormack and dos Santos Silva, 2006;Vachon et al, 2007;Galukande and Kiguli-Malwadde, 2012).…”

“…Moreover, high density breasts in mammography are at a higher risk for breast cancer (McCormack and dos Santos Silva, 2006;Vachon et al, 2007;Heine et al, 2008;Zulfiqar et al, 2011;Phipps et al, 2012). When using breast density as a predictor of breast cancer risk, the majority of the studies report 2-to 6-fold increased risks for the highest group in comparison with the lowest risk categories (McCormack and dos Santos Silva, 2006;Vachon et al, 2007;Galukande and Kiguli-Malwadde, 2012). Density in mammography has been accepted as one of the strongest risk factor for the cancer (Hanna and Diorio, 2013), stronger than nulliparity and early menarche, implying some independency to estrogen mediated effects in its carcinogenesis (Galukande and Kiguli-Malwadde, 2012).…”