Katja Pinker MD, Presenter: Nothing to Disclose

Nicholas Mark Perry MD, Abstract Co-Author: Nothing to Disclose

Sue Elizabeth Milner BSC, Abstract Co-Author: Nothing to Disclose

Kefah Mokbel MD, Abstract Co-Author: Nothing to Disclose

Stephen W Duffy, Abstract Co-Author: Nothing to Disclose

To validate the predictive power for determining breast cancer risk of an automated breast density measurement system with full-field digital mammography (FFDM).

200 histopathologically verified breast cancer cases and 200 age-matched healthy controls, all imaged with FFDM, were included in this retrospective study. Density was measured separately on mediolateral oblique and craniocaudal images using an integral automated volumetric breast density measurement system (Hologic Quantra). For each cancer case, the contralateral mammogram was used to assess density. Each cancer case was matched to a control case by date of birth, age at examination and laterality of mammogram used for density determination. Breast density (percentage of fibroglandular tissue) was analyzed by Quantra. Data were analyzed by conditional logistic regression to determine the effect on breast cancer risk.

Percentage of breast density ranged from 6% to 63%. Density declined significantly with age (p<0.001). Overall, there was no significant association of density with risk of breast cancer (p=0.4). There was a suggestive increase in risk with dense volume higher than 35% (OR=1.80, 95% CI 0.96-3.39, p=0.07). There was significant heterogeneity by age in the effect of density on risk (p=0.04). In women aged <50, density was significantly associated with increased risk (p=0.02), with odds ratios of 6.06, 3.98 and 10.59 for density volumes of 15-24%, 25-34% and ≥35% respectively, relative to those with <15%. In women aged 50 years or more there was no association of density with risk (p=0.5). This may relate to the higher densities and greater range of densities in women aged less than 50 (median 25%, interquartile range 18-32%) compared to the older group (median 17%, interquartile range 12-24%).

Quantra automated volumetric breast density measurement is strongly associated with breast cancer risk in women aged under 50, but not in women aged 50 years or over.

An integrated Quantra system with FFDM correlates density with risk in women under 50 and may be useful in predicting those who might benefit from additional imaging modalities.

Pinker, K, Perry, N, Milner, S, Mokbel, K, Duffy, S, Validation of a New Automated Volumetric Breast Density Measurement System as a Marker of Breast Cancer Risk.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8005120.html