Area and volumetric breast density measures are strong risk factors for breast cancer (BC). We compared breast density estimates from a publically available, fully-automated software tool, the Laboratory for Individualized Breast Radiodensity Assessment (LIBRA), which can be run both on “For Processing” and “For Presentation” digital mammogram formats, to those from commercial software, which are only run on “For Processing” format.
METHOD AND MATERIALSDigital mammograms in both formats were obtained prior to diagnosis on 437 incident BC cases and 1225 age-matched controls from a large screening mammography practice. LIBRA estimates included dense area (DA) and percent density (PD) averaged from four mammogram views of both digital mammogram formats. Volumetric percent density (VPD) and dense volume (DV) estimates were also obtained on four views of “For Processing” formats only, using Volpara (Matakina Ltd.) and Quantra (Hologic Inc.) software. We compared density measures using Pearson correlations (R) among controls, and odds ratios and 95% confidence intervals (OR (95%CI)) for BC per standard deviation (SD) density measure from conditional logistic regression, adjusting for age and body mass index.
RESULTSLIBRA PD showed strong correlation with Volpara VPD (R=0.80-0.87), but moderate correlation with Quantra VPD (R=0.53-0.60). LIBRA DA was low to moderately correlated with Quantra DV (R=0.28-0.52) and Volpara DV (R=0.52-0.65). The strongest associations of LIBRA with BC were seen with “For Presentation” density measures, OR=1.3 (1.1-1.5) per SD of PD and OR=1.2 (1.1-1.4) per SD of DA, while estimates from “For Processing” images were attenuated: OR=1.1 (1.0-1.3) and OR=1.1 (0.97-1.2), per SD of PD and DA respectively. For commercial measures, risk estimates for VPD with BC were slightly larger (OR=1.4 (1.2-1.6) and OR=1.3 (1.1-1.4) per SD VPD) than DV (OR=1.2 (1.1-1.4) and OR=1.2 (1.0-1.3) per SD DV) for Volpara and Quantra respectively, but not significantly different.
CONCLUSIONOur results confirm prior smaller studies showing that LIBRA, a publically available, fully-automated breast density estimation software run on readily available “For Presentation” mammograms, has similar BC associations as commercial software.
CLINICAL RELEVANCE/APPLICATIONA publically available, fully-automated software utilizing “For Presentation” images could further enable research on quantitative density measures in personalized screening and cancer risk assessment.