Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Dec 19;18(1):130.
doi: 10.1186/s13058-016-0787-0.

Mammographic density assessed on paired raw and processed digital images and on paired screen-film and digital images across three mammography systems

Affiliations

Mammographic density assessed on paired raw and processed digital images and on paired screen-film and digital images across three mammography systems

Anya Burton et al. Breast Cancer Res. .

Abstract

Background: Inter-women and intra-women comparisons of mammographic density (MD) are needed in research, clinical and screening applications; however, MD measurements are influenced by mammography modality (screen film/digital) and digital image format (raw/processed). We aimed to examine differences in MD assessed on these image types.

Methods: We obtained 1294 pairs of images saved in both raw and processed formats from Hologic and General Electric (GE) direct digital systems and a Fuji computed radiography (CR) system, and 128 screen-film and processed CR-digital pairs from consecutive screening rounds. Four readers performed Cumulus-based MD measurements (n = 3441), with each image pair read by the same reader. Multi-level models of square-root percent MD were fitted, with a random intercept for woman, to estimate processed-raw MD differences.

Results: Breast area did not differ in processed images compared with that in raw images, but the percent MD was higher, due to a larger dense area (median 28.5 and 25.4 cm2 respectively, mean √dense area difference 0.44 cm (95% CI: 0.36, 0.52)). This difference in √dense area was significant for direct digital systems (Hologic 0.50 cm (95% CI: 0.39, 0.61), GE 0.56 cm (95% CI: 0.42, 0.69)) but not for Fuji CR (0.06 cm (95% CI: -0.10, 0.23)). Additionally, within each system, reader-specific differences varied in magnitude and direction (p < 0.001). Conversion equations revealed differences converged to zero with increasing dense area. MD differences between screen-film and processed digital on the subsequent screening round were consistent with expected time-related MD declines.

Conclusions: MD was slightly higher when measured on processed than on raw direct digital mammograms. Comparisons of MD on these image formats should ideally control for this non-constant and reader-specific difference.

Keywords: Breast cancer; Breast density; Image processing; Mammographic density assessment; Methods.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Examples of raw and processed images from Hologic, GE and Fuji digital mammography systems. a Raw and e processed paired images captured on GE Senographe Essential (G2, UK). b Raw and f processed paired images captured on Hologic Lorad Selenia (H1, Chile). c Raw and g processed paired images captured on Fuji CR (F1). d Screen-film image and h its paired Fujifilm CR processed image (SFM/digital set F2, Australia). CC craniocaudal, L left, MLO mediolateral oblique, R right
Fig. 2
Fig. 2
Scatter plot of paired √DA readings measured on processed (y axis) vs raw (x axis) digital images, by reader and system. Dashed lines, equality (if DA from processed images was read identically to raw images); blue dots, modelled linear conversion. Reader-specific and system-specific calibration equations for the conversion of raw √DA to processed √DA are supplied in (Additional file 7: Information 2). √DA square root of dense area, GE General Electric

Similar articles

Cited by

References

    1. Boyd NF, Guo H, Martin LJ, Sun L, Stone J, Fishell E, et al. Mammographic density and the risk and detection of breast cancer. N Engl J Med. 2007;356:227–36. doi: 10.1056/NEJMoa062790. - DOI - PubMed
    1. Warwick J, Birke H, Stone J, Warren RM, Pinney E, Brentnall AR, et al. Mammographic breast density refines Tyrer-Cuzick estimates of breast cancer risk in high-risk women: findings from the placebo arm of the International Breast Cancer Intervention Study I. Breast Cancer Res. 2014;16:451. doi: 10.1186/s13058-014-0451-5. - DOI - PMC - PubMed
    1. Cuzick J, Warwick J, Pinney E, Duffy SW, Cawthorn S, Howell A, et al. Tamoxifen-induced reduction in mammographic density and breast cancer risk reduction: a nested case–control study. J Natl Cancer Inst. 2011;103:744–52. doi: 10.1093/jnci/djr079. - DOI - PubMed
    1. Schousboe JT, Kerlikowske K, Loh A, Cummings SR. Personalizing mammography by breast density and other risk factors for breast cancer: analysis of health benefits and cost-effectiveness. Ann Intern Med. 2011;155:10–20. doi: 10.7326/0003-4819-155-1-201107050-00003. - DOI - PMC - PubMed
    1. Nickson C, Arzhaeva Y, Aitken Z, Elgindy T, Buckley M, Li M, et al. AutoDensity: an automated method to measure mammographic breast density that predicts breast cancer risk and screening outcomes. Breast Cancer Res. 2013;15:R80. doi: 10.1186/bcr3474. - DOI - PMC - PubMed

Publication types