Role of dynamic contrast‐enhanced MRI in evaluating the association between contralateral parenchymal enhancement and survival outcome in ER‐positive, HER2‐negative, node‐negative invasive breast cancer

摘要

Background Background parenchymal enhancement (BPE) on dynamic contrast‐enhanced (DCE)‐MRI has been associated with breast cancer risk, both based on qualitative and quantitative assessments. Purpose To investigate whether BPE of the contralateral breast on preoperative DCE‐MRI is associated with therapy outcome in ER‐positive, HER2‐negative, node‐negative invasive breast cancer. Study Type Retrospective. Population In all, 289 patients with unilateral ER‐positive, HER2‐negative, node‐negative breast cancer larger than 5?mm. Field Strength/Sequence 3T, T 1 ‐weighted DCE sequence. Assessment BPE of the contralateral breast was assessed qualitatively by two dedicated radiologists and quantitatively (using region‐of‐interest and automatic breast segmentation). Statistical Tests Cox regression analysis was used to determine associations with recurrence‐free survival (RFS) and distant metastasis‐free survival (DFS). Interobserver variability for parenchymal enhancement was assessed using kappa statistics and intraclass correlation coefficient (ICC). Results The median follow‐up time was 75.8 months. Multivariate analysis showed receipt of total mastectomy (hazard ratio [HR]: 5.497) and high Ki‐67 expression level (HR: 5.956) were independent factors associated with worse RFS ( P ??0.05). Only a high Ki‐67 expression level was associated with worse DFS (HR: 3.571, P ?=?0.045). BPE assessments were not associated with outcome (RFS [qualitative BPE: P ?=?0.75, 0.92 for readers 1 and 2; quantitative BPE: P ?=?0.38‐0.99], DFS, [qualitative BPE: P ?=?0.41, 0.16 for readers 1 and 2; quantitative BPE: P ?=?0.68‐0.99]). For interobserver variability, there was good agreement between qualitative (κ?=?0.700) and good to perfect agreement for most quantitative parameters of BPE. Data Conclusion Contralateral BPE showed no association with survival outcome in patients with ER‐positive, HER2‐negative, node‐negative invasive breast cancer. A high Ki‐67 expression level was associated with both worse recurrence‐free and distant metastasis‐free survival. Level of Evidence: 3 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2018;48:1678–1689