Breast Center, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba, 296-8602, Japan.
Breast Cancer. 2013 Jan;20(1):13-20. doi: 10.1007/s12282-011-0312-3. Epub 2011 Nov 23.
There has been dramatic progress in MRI technology during the past 20 years, and the rate of detection and diagnostic accuracy in regard to intraductal carcinoma and ductal carcinoma in situ (DCIS) have been increasing. First, we present MRI images of intraductal carcinomas and the terminology in the second edition of the BI-RADS-MRI to describe them. Next, we examined the data in our institution in regard to the following: (1) the DCIS detection rate, (2) the proportions of breast cancer and DCIS in MR-guided vacuum-assisted biopsies (VAB), (3) evaluation of the extent of intraductal carcinoma, and (4) diagnosis of extension of intraductal carcinoma into the nipple. MR images were acquired by performing a 1-min interval dynamic study with a 1.5-T MR scanner. The same radiologist evaluated the MRI in all of the cases. MR-guided VAB was performed by using a commercially available biopsy system. (1) The DCIS detection rate was 95% (148/156), and the DCIS lesions that MRI was unable to detect were low grade in 5 cases, intermediate grade in 2 cases, and high grade in 1 case. (2) The proportion of MR-guided VAB specimens that were breast cancer was 36% (71/200), and the proportion of breast cancers that were DCIS was 82% (58/71). (3) The proportion of margin-positive specimens in the 100 breasts in which breast-conserving surgery was performed was 11% (11/100), and the proportion in which MRI was the cause of the margin being positive was a mere 4% (4/100). (4) The positive predictive value of periductal enhancement and linear enhancement for a diagnosis of intraductal extension into the nipple was 83% (10/12) and 43% (3/7), respectively. Their negative predictive value was 100% (58/58). We concluded that MRI is a very useful examination for the diagnosis of intraductal carcinoma, and that it is important to become thoroughly familiar with the BI-RADS-MRI terminology and accurate interpretation methods.
在过去的 20 年中，MRI 技术取得了巨大的进展，导管内癌和导管原位癌（DCIS）的检出率和诊断准确性都在提高。首先，我们展示了导管内癌的 MRI 图像和第二版 BI-RADS-MRI 中的术语，以描述它们。接下来，我们检查了我们机构的数据，包括：（1）DCIS 的检出率，（2）乳腺肿瘤和 DCIS 在 MRI 引导下真空辅助活检（VAB）中的比例，（3）导管内癌范围的评估，（4）导管内癌延伸至乳头的诊断。MR 图像是在 1.5T MR 扫描仪上进行 1 分钟间隔动态研究获得的。所有病例均由同一位放射科医生进行 MRI 评估。MR 引导下的 VAB 使用市售的活检系统进行。（1）DCIS 的检出率为 95%（148/156），MRI 未能检出的 DCIS 病变有 5 例为低级别，2 例为中级别，1 例为高级别。（2）MRI 引导下 VAB 标本中乳腺癌的比例为 36%（71/200），乳腺癌中 DCIS 的比例为 82%（58/71）。（3）100 例接受保乳手术的乳房中，边缘阳性标本的比例为 11%（11/100），而 MRI 导致边缘阳性的比例仅为 4%（4/100）。（4）导管周围强化和线性强化对诊断乳头内导管延伸的阳性预测值分别为 83%（10/12）和 43%（3/7），阴性预测值均为 100%（58/58）。我们得出结论，MRI 是诊断导管内癌非常有用的检查方法，熟悉 BI-RADS-MRI 术语和准确的解释方法非常重要。
