CRUK Cancer Imaging Centre, The Institute of Cancer Research and Royal Marsden Foundation Trust, London, UK.
The Royal Marsden NHS Foundation Trust, Sutton, UK.
Eur Radiol. 2023 Sep;33(9):6204-6212. doi: 10.1007/s00330-023-09592-2. Epub 2023 Apr 5.
To investigate whether MRI-based measurements of fibro-glandular tissue volume, breast density (MRBD), and background parenchymal enhancement (BPE) could be used to stratify two cohorts of healthy women: BRCA carriers and women at population risk of breast cancer.
Pre-menopausal women aged 40-50 years old were scanned at 3 T, employing a standard breast protocol including a DCE-MRI (35 and 30 participants in high- and low-risk groups, respectively). The dynamic range of the DCE protocol was characterised and both breasts were masked and segmented with minimal user input to produce measurements of fibro-glandular tissue volume, MRBD, and voxelwise BPE. Statistical tests were performed to determine inter- and intra-user repeatability, evaluate the symmetry between metrics derived from left and right breasts, and investigate MRBD and BPE differences between the high- and low-risk cohorts.
Intra- and inter-user reproducibility in estimates of fibro-glandular tissue volume, MRBD, and median BPE estimations were good, with coefficients of variation < 15%. Coefficients of variation between left and right breasts were also low (< 25%). There were no significant correlations between fibro-glandular tissue volume, MRBD, and BPE for either risk group. However, the high-risk group had higher BPE kurtosis, although linear regression analysis did not reveal significant associations between BPE kurtosis and breast cancer risk.
This study found no significant differences or correlations in fibro-glandular tissue volume, MRBD, or BPE metrics between the two groups of women with different levels of breast cancer risk. However, the results support further investigation into the heterogeneity of parenchymal enhancement.
• A semi-automated method enabled quantitative measurements of fibro-glandular tissue volume, breast density, and background parenchymal enhancement with minimal user intervention. • Background parenchymal enhancement was quantified over the entire parenchyma, segmented in pre-contrast images, thus avoiding region selection. • No significant differences and correlations in fibro-glandular tissue volume, breast density, and breast background parenchymal enhancement were found between two cohorts of women at high and low levels of breast cancer risk.
探究基于 MRI 的纤维腺体组织容积、乳腺密度（MRBD）和背景实质强化（BPE）测量值能否用于分层 2 组健康女性：BRCA 携带者和乳腺癌人群风险女性。
对 40-50 岁的绝经前女性进行 3T 扫描，采用标准乳腺方案，包括 DCE-MRI（高风险组和低风险组分别有 35 名和 30 名参与者）。DCE 方案的动态范围进行了特征描述，左右乳房均采用最小用户输入进行掩模和分割，以生成纤维腺体组织容积、MRBD 和体素 BPE 的测量值。进行统计检验以确定组内和组间的可重复性，评估左右乳房衍生指标的对称性，以及调查高风险和低风险队列之间的 MRBD 和 BPE 差异。
纤维腺体组织容积、MRBD 和中位数 BPE 估计值的组内和组间可重复性均良好，变异系数<15%。左右乳房之间的变异系数也较低（<25%）。对于任一风险组，纤维腺体组织容积、MRBD 和 BPE 之间均无显著相关性。然而，高风险组的 BPE 峰度较高，尽管线性回归分析并未显示 BPE 峰度与乳腺癌风险之间存在显著关联。
本研究发现两组不同乳腺癌风险女性之间的纤维腺体组织容积、MRBD 或 BPE 指标无显著差异或相关性。但是，结果支持进一步研究实质增强的异质性。
• 半自动化方法能够对纤维腺体组织容积、乳腺密度和背景实质强化进行定量测量，仅需最小的用户干预。• 背景实质强化是在预对比图像中对整个实质进行量化分割，从而避免了区域选择。• 在高风险和低风险两组女性中，纤维腺体组织容积、乳腺密度和乳腺背景实质强化之间未发现显著差异和相关性。
