6th International Workshop on Breast Densitometry and Breast ...

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6 th <strong>International</strong> <strong>Workshop</strong> on Breast Densitometry
and Breast Cancer Risk Assessment
VALIDATION OF A FULLY AUTOMATED, HIGH THROUGHPUT MAMMOGRAPHIC
DENSITY MEASUREMENT TOOL FOR USE WITH PROCESSED DIGITAL
MAMMOGRAMS
AM Couwenberg, CH van Gils, J Li, R Pijnappel, RK Charaghvandi, M Hartman, HM Verkooijen
Introduction: Recently, a public domain image-processing software (ImageJ) tool was developed to
mimic Cumulus mammographic density readings. This fully-automated method has been validated for
digitized film screen mammograms (JM Li et al. 2012). i Here we validate the Image J density reading tool
in processed full field digital mammograms (FFDM), which are currently the most commonly available
image types. We also correlate Image J readings with the clinically widely-used BIRADS density
classification.
Methods: This study includes Dutch women who underwent a FFDM mammography between 2001 and
2011 at the University Medical Center Utrecht, the Netherlands. Only processed images were available.
We composed a training set for model building (n=170 women, 331 images MLO and CC view of the
contralateral breast) and a test set for model assessment (530 women, 4,429 images MLO and CC view of
the contralateral breast). The training set was read with Cumulus by one trained reader and used to build
the automated Image J mammographic density model. This model was used for the density assessment in
the test set. These automated density readings were compared with BIRADS density readings by a
dedicated breast radiologist. We used Pearson product-moment correlation coefficient (r) to compare
Cumulus measurements with the automated measurements in the training set. Correlation and of the
automated method with BIRADS density readings in the test set was estimated using Spearman
correlation coefficient. As a further validation, we investigated the association between breast cancer risk
factors and the automated density measurements for the patients in our test set, using generalized linear
models.
Results: We observed a high correlation between the automated method and Cumulus (r=0.90 95% Cl:
0.86 – 0.93). We also found a high correlation between the automated measure and the BIRADS density
classification in the test set (spearman r= 0.862). Women with a higher density as measured with the
automated method, were significantly younger, more often premenopausal, had a lower number of
children, and more often a benign breast lesions or a family history of breast cancer.
Conclusion: We demonstrated that the high-throughput automated density assessment tool, based on the
analysis of the established method of Cumulus and previously validated on digitized film-screen
mammograms, can be used on processed digital mammograms. Its results also strongly correlate with the
clinically widely-used BIRADS density readings and with established breast cancer risk factors.
ABSTRACTS
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1 Li et al. High-throughput mammographic-density measurement: a tool for risk prediction of breast cancer.
Breast Cancer Research 2012, 14:R114.
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