OBJECTIVE. The purpose of this study was to investigate the diagnostic performance of unenhanced MRI in detecting breast cancer and to assess the impact of double reading. MATERIALS AND METHODS. A total of 116 breasts of 67 women who were 36-89 years old were studied at 1.5 T using an unenhanced protocol including axial Tl-weight-ed gradient-echo, T2-weighted STIR, and echo-planar diffusion-weighted imaging (DWI). Two blinded readers (Rl and R2) independently evaluated unenhanced images using the BI-RADS scale. A combination of pathology and negative follow-up served as the reference standard. McNemar and kappa statistics were used. RESULTS. Per-breast cancer prevalence was 37 of 116 (32%): 30 of 37 (81%) invasive ductal carcinoma, five of 37 (13%) ductal carcinoma in situ, and two of 37 (6%) invasive lobular carcinoma. Per-breast sensitivity of unenhanced MRI was 29 of 37 (78%) forRl, 28 of 37 (76%) for R2, and 29 of 37 (78%) for double reading. Specificity was 71 of 79 (90%) for both Rl and R2 and 69 of 79 (87%) for double reading. Double reading did not provide a significant increase in sensitivity. Interobserver agreement was almost perfect (Cohen κ = 0.873). CONCLUSION. An unenhanced breast MRI protocol composed of Tl-weighted gradient echo, T2-weighted STIR, and echo-planar DWI enabled breast cancer detection with sensitivity of 76-78% and specificity of 90% without a gain in sensitivity from double reading.
- Breast cancer
- Diffusion-weighted imaging (DWl)
- Double reading
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging