Computed diffusion- weighted imaging with a low-apparent diffusion coefficient- pixel cut- off technique for breast cancer detection

Objective: This study aimed to compare the image quality and diagnostic performance of computed diffusion-weighted imaging (DWI) with low-apparent diffusion coefficient (ADC)-pixel cut-off technique (cDWI cut-off) and actual measured DWI (mDWI).Methods: Eighty-seven consecutive patients with malignant breast lesions and 72 with negative breast lesions who underwent breast MRI were retrospectively evaluated. Computed DWI with high b-values of 800, 1200, and 1500 s/mm(2) and ADC cut-off thresholds of none, 0, 0.3, and 0.6 (x10(-3) mm(2)/s) were generated from DWI with two b-values (0 and 800 s/mm(2)). To identify the optimal conditions, two radiologists evaluated the fat suppression and lesion reduction failure using a cut-off technique. The contrast between breast cancer and glandular tissue was evaluated using region of interest analysis. Three other board-certified radiologists independently assessed the optimised cDWI cut-off and mDWI data sets. Diagnostic performance was evaluated using receiver operating characteristic (ROC) analysis.Results: When an ADC cut-off threshold of 0.3 or 0.6 (x 10(-3) mm(2)/s) was applied, fat suppression improved significantly (p < .05). The contrast of the cDWI cut-off with a b-value of 1200 or 1500 s/mm(2) was better than the mDWI (p < .01). The ROC area under the curve for breast cancer detection was 0.837 for the mDWI and 0.909 for the cDWI cut-off (p < .01).Conclusion: The cDWI cut-off provided better diagnostic performance than mDWI for breast cancer detection.