Department of Radiology, Seattle Cancer Care Alliance, WA 98109, USA.
AJR Am J Roentgenol. 2012 Apr;198(4):W373-80. doi: 10.2214/AJR.10.6272.
Breast density is documented to reduce sensitivity and specificity of mammography. However, little is known regarding the effect of normal background parenchymal enhancement on accuracy of breast MRI. The purpose of this study was to evaluate the effect of background parenchymal enhancement on MRI diagnostic performance.
A review of our established MRI data identified all women undergoing breast MRI from March 1, 2006, through June 30, 2007. Prospectively reported background parenchymal enhancement categories of minimal, mild, moderate, or marked (anticipated BI-RADS MRI lexicon definitions) and assessments were extracted from the database for each patient. Outcomes were determined by pathologic analysis, imaging, and linkage with the regional tumor registry with a minimum of 24 months of follow-up. Patients were dichotomized into categories of minimal or mild versus moderate or marked background parenchymal enhancement. Associations with patient age, abnormal interpretation rate, positive biopsy rate, cancer yield, sensitivity, and specificity were compared using chi-square and z score tests.
The study cohort included 736 women. Moderate or marked background parenchymal enhancement was significantly more frequent among patients younger than 50 years compared with those 50 years old and older (39.7% vs 18.9%; p < 0.0001). Moderate or marked background parenchymal enhancement was also associated with a higher abnormal interpretation rate compared with minimal or mild background parenchymal enhancement (30.5% vs 23.3%; p = 0.046). Positive biopsy rate, cancer yield, sensitivity, and specificity were not significantly different according to background parenchymal enhancement category.
Increased background parenchymal enhancement on breast MRI is associated with younger patient age and higher abnormal interpretation rate. However, it is not related to significant differences in positive biopsy rate, cancer yield, sensitivity, or specificity of MRI.
乳腺密度被证明会降低乳房 X 光摄影的敏感性和特异性。然而，关于正常背景实质增强对乳房 MRI 准确性的影响知之甚少。本研究的目的是评估背景实质增强对 MRI 诊断性能的影响。
对我们建立的 MRI 数据进行回顾性分析，确定了 2006 年 3 月 1 日至 2007 年 6 月 30 日期间所有接受乳房 MRI 的女性。从数据库中提取每位患者的背景实质增强的最小、轻度、中度或明显（预期 BI-RADS MRI 词汇定义）类别和评估。通过病理分析、成像以及与区域肿瘤登记处的链接来确定结果，随访时间至少为 24 个月。将患者分为背景实质增强最小或轻度与中度或明显两组。使用卡方检验和 z 分数检验比较患者年龄、异常解读率、阳性活检率、癌症检出率、敏感性和特异性的相关性。
本研究队列包括 736 名女性。与 50 岁及以上的患者相比，50 岁以下的患者中度或明显的背景实质增强更为常见（39.7%比 18.9%；p<0.0001）。与背景实质增强最小或轻度相比，中度或明显的背景实质增强也与更高的异常解读率相关（30.5%比 23.3%；p=0.046）。阳性活检率、癌症检出率、敏感性和特异性与背景实质增强类别无显著差异。
乳房 MRI 上的背景实质增强增加与患者年龄较小和异常解读率较高有关。然而，它与阳性活检率、癌症检出率、敏感性或特异性的 MRI 无显著差异。
