Department of Radiology, University of Washington, Seattle Cancer Care Alliance, Seattle, Washington 98109-1023, USA.
J Magn Reson Imaging. 2010 Mar;31(3):562-70. doi: 10.1002/jmri.22078.
To investigate the diagnostic performance of diffusion-weighted imaging (DWI) for mammographically and clinically occult breast lesions.
The study included 91 women with 118 breast lesions (91 benign, 12 ductal carcinoma in situ [DCIS], 15 invasive carcinoma) initially detected on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and assigned BI-RADS category 3, 4, or 5. DWI was acquired with b = 0 and 600 s/mm(2). Lesion visibility was assessed on DWI. Apparent diffusion coefficient (ADC) values were compared between malignancies, benign lesions, and normal (no abnormal enhancement on DCE-MRI) breast tissue, and the diagnostic performance of DWI was assessed based on ADC thresholding.
Twenty-four of 27 (89%) malignant and 74/91 (81%) benign lesions were hyperintense on the b = 600 s/mm(2) diffusion-weighted images. Both DCIS (1.33 +/- 0.19 x 10(-3) mm(2)/s) and invasive carcinomas (1.30 +/- 0.27 x 10(-3)mm(2)/s) were lower in ADC than benign lesions (1.71 +/- 0.43 x 10(-3)mm(2)/s; P < 0.001), and each lesion type was lower in ADC than normal tissue (1.90 +/- 0.38 x 10(-3)mm(2)/s, P <or= 0.001). Receiver operating curve (ROC) analysis showed an area under the curve (AUC) of 0.77, and sensitivity = 96%, specificity = 55%, positive predictive value (PPV) = 39%, and negative predictive value (NPV) = 98% for an ADC threshold of 1.60 x 10(-3)mm(2)/s.
Many mammographically and clinically occult breast carcinomas were visibly hyperintense on diffusion-weighted images, and ADC enabled differentiation from benign lesions. Further studies evaluating DWI while blinded to DCE-MRI are necessary to assess the potential of DWI as a noncontrast breast screening technique.
研究扩散加权成像（DWI）在乳腺钼靶和临床隐匿性病变中的诊断性能。
本研究纳入了 91 名女性的 118 个乳腺病变（91 个良性、12 个导管原位癌[DCIS]、15 个浸润性癌），这些病变最初是在动态对比增强磁共振成像（DCE-MRI）上发现的，且 BI-RADS 分类为 3、4 或 5 类。DWI 采用 b 值为 0 和 600 s/mm²。在 DWI 上评估病变的可见性。比较恶性肿瘤、良性病变和正常（DCE-MRI 未见异常增强）乳腺组织之间的表观扩散系数（ADC）值，并根据 ADC 阈值评估 DWI 的诊断性能。
27 个恶性病变中的 24 个（89%）和 91 个良性病变中的 74 个（81%）在 b 值为 600 s/mm²的弥散加权图像上呈高信号。DCIS（1.33±0.19×10（-3）mm²/s）和浸润性癌（1.30±0.27×10（-3）mm²/s）的 ADC 值均低于良性病变（1.71±0.43×10（-3）mm²/s；P＜0.001），且每种病变类型的 ADC 值均低于正常组织（1.90±0.38×10（-3）mm²/s，P≤0.001）。受试者工作特征曲线（ROC）分析显示，曲线下面积（AUC）为 0.77，当 ADC 阈值为 1.60×10（-3）mm²/s 时，敏感性为 96%，特异性为 55%，阳性预测值（PPV）为 39%，阴性预测值（NPV）为 98%。
许多乳腺钼靶和临床隐匿性乳腺癌在弥散加权图像上呈明显高信号，ADC 有助于与良性病变鉴别。进一步的研究需要在对 DCE-MRI 不知情的情况下评估 DWI，以评估 DWI 作为非对比乳腺筛查技术的潜力。
