Department of Radiology, College of Medicine, Korea University, Guro Korea University Hospital, Gurogu, Seoul, Korea.
Radiographics. 2010 Oct;30(6):1689-702. doi: 10.1148/rg.306105511.
Most well-circumscribed breast masses are benign lesions such as cysts, fibroadenomas, and intramammary lymph nodes. Nevertheless, 10%-20% of breast malignancies are well-circumscribed masses, and these malignancies include papillary, mucinous, medullary, and metaplastic carcinomas, as well as malignant phyllodes tumors. Therefore, it is important to differentiate these well-circumscribed breast malignancies from benign breast lesions, but it is not easy to do so with conventional imaging modalities such as mammography and ultrasonography (US). As an emerging adjunctive imaging method, magnetic resonance (MR) imaging has substantial potential in characterizing well-circumscribed breast carcinomas. Analysis of the lesion signal intensity on nonenhanced T2-weighted MR images, determination of the enhancement pattern, and kinetic curve assessment can greatly help differentiate malignant from benign well-circumscribed breast lesions. Therefore, breast MR imaging can play a substantial role in distinguishing between well-circumscribed benign and malignant breast lesions, especially in cases that are difficult to diagnose by using conventional imaging. In this article, the MR imaging findings of the subtypes of well-circumscribed malignant breast lesions-intracystic papillary carcinoma, invasive papillary carcinoma, mucinous carcinoma, medullary carcinoma, metaplastic carcinoma, and malignant phyllodes tumor-are described and correlated with the histopathologic, mammographic, and US findings.
大多数边界清楚的乳腺肿块是良性病变，如囊肿、纤维腺瘤和乳腺内淋巴结。然而，10%-20%的乳腺恶性肿瘤是边界清楚的肿块，这些恶性肿瘤包括乳头状癌、黏液癌、髓样癌和间变性癌，以及恶性叶状肿瘤。因此，区分这些边界清楚的乳腺恶性肿瘤与良性乳腺病变非常重要，但通过常规成像方式（如乳腺 X 线摄影和超声检查）很难做到这一点。作为一种新兴的辅助成像方法，磁共振（MR）成像在描述边界清楚的乳腺癌方面具有很大的潜力。分析非增强 T2 加权 MR 图像上的病变信号强度、确定增强模式和评估动力学曲线可以极大地帮助区分恶性和良性边界清楚的乳腺病变。因此，乳腺 MR 成像在区分边界清楚的良性和恶性乳腺病变方面可以发挥重要作用，特别是在常规成像难以诊断的情况下。本文描述了边界清楚的恶性乳腺病变各亚型（囊内乳头状癌、浸润性乳头状癌、黏液癌、髓样癌、间变性癌和恶性叶状肿瘤）的 MR 成像表现，并与组织病理学、乳腺 X 线摄影和超声检查结果相关联。
