Additional value of diffusion-weighted imaging to evaluate multifocal and multicentric breast cancer detected using pre-operative breast MRI

作者：Song Sung Eun; Park Eun Kyung; Cho Kyu Ran^*; Seo Bo Kyoung; Woo Ok Hee; Jung Seung Pil; Cho Sung Bum

来源：European Radiology, 2017, 27(11): 4819-4827.

DOI：10.1007/s00330-017-4898-5

• Breast neoplasm
• Diffusion-weighted imaging
• Breast magnetic resonance imaging
• Apparent diffusion coefficient
• Staging

Objectives To investigate whether diffusion-weighted imaging (DWI) aids pre-operative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to evaluate additional lesions in breast cancer patients.
Methods DCE-MRI andDWI were performed on 131 lesions, with available histopathological results. The apparent diffusion coefficient (ADC) of each lesion was measured, and the cut-off value for differentiation between malignant and benign lesions was calculated. A protocol combining the ADC cut-off value with DCE-MRI was validated in a cohort of 107 lesions in 77 patients.
Results When an ADC cut-off value of 1.11 x 10(-3) mm(2)/s from the development cohort was applied to the additional lesions in the validation cohort, the specificity increased from 18.9% to 67.6% (P < 0.001), and the diagnostic accuracy increased from 61.7% to 82.2% (P = 0.05), without significant loss of sensitivity (98.6% vs. 90.0%, P = 0.07). The negative predictive values of lesions in the same quadrant had decreased, as had those of lesions >= 1 cm in diameter. The ADC cut-off value in the validation cohort was 1.05 x 10(-3) mm(2)/ s.
Conclusions Additional implementation of DWI for breast lesions in pre-operative MRI can help to obviate unnecessary biopsies by increasing specificity. However, to avoid missing cancers, clinicians should closely monitor lesions located in the same quadrant or lesions >= 1 cm.