Role of diffusion weighted images combined with breast MRI in improving the detection and differentiation of breast lesions

Abstract

Purpose: To assess the impact of diffusion-weighted images as a complementary tool to conventional breast MRI in the evaluation of various breast lesions. Materials and methods: From November 2013 to June 2014 thirty patients referred from breast clinic by breast symptoms and abnormal sono-mammography lesions have been included in this study. All patients underwent breast DCE-MRI combined with DWI and the results were compared with the histopathological examination which was used as the standard diagnostic method. Results: The study included thirty patients complaining of breast lesions, 35 lesions were detected, according to the histopathological analysis, there were 20 malignant lesions (57.14%) and 15 benign lesions (42.86%). DCE-MRI had a sensitivity of 80%, a specificity of 73.33%, PPV of 80%, NPV of 73.3% and accuracy of 77.14%. The malignant lesions showed a mean ADC value of 1.03 ± 0.35. Alternatively, the benign lesions showed a mean ADC value of 1.38 ± 0.26. Among the 20 malignant lesions, 17 lesions showed an ADC value ⩽1.20 mm2/s and 3 lesions showed an ADC value >1.20 mm2/s. While among the 15 benign lesions, 14 lesions showed ADC value >1.20 mm2/s and 1 lesion showed an ADC value ⩽1.20. The ROC curve showed that the best ADC cut-off value to differentiate between benign and malignant lesions was 1.2 mm2/s (P < 0.001) with sensitivity, specificity, PPV, NPV and accuracy of 85%, 93.33%, 94.4%, 82.4% and 90.3% respectively. Conclusion: DWI had a higher sensitivity and specificity than DCE-MRI with ADC cut off value 1.20. This value was a sensitive and specific parameter in differentiating benign and malignant breast lesions.

Keywords

• Breast masses
• Breast cancer
• Breast MRI with DWI