Diffusion-weighted MRI as an adjunct to mammography in women under 50 years of age: An initial study

Purpose: To evaluate diffusion-weighted magnetic resonance (DW) imaging as an adjunct to mammography for the detection of small invasive breast cancer. Materials and Methods: Institutional review board standards were followed for this retrospective study. We performed both breast DW imaging and mammography on 25 women under 50 years of age with pathologically proven T1 breast cancer and on 21 healthy women under 50 years of age. Four offsite radiologists blind to the clinical information independently interpreted the mammograms and DW images and then classified their confidence level regarding the presence of breast cancer. The composite area under receiver operating characteristic curve (AUC), of mammography alone, DW imaging alone, and the combination of DW imaging and mammography (DWI/Cal) were calculated. Results: The AUC of composite ROC curves of mammography, DW imaging, DWI/Cal combination, was 0.79 (95% CI, 0.72-0.87), 0.86 (95% CI, 0.84-0.87), and 0.96 (95% CI, 0.92-1.00), respectively. Conclusion: DW imaging may be a useful adjunct to mammography in the detection of small invasive breast cancer in women under 50 years of age.