Time-to-enhancement at ultrafast breast DCE-MRI: potential imaging biomarker of tumour aggressiveness

Objectives This study was conducted in order to investigate whether there is a correlation between the time-to-enhancement (TTE) in ultrafast MRI and histopathological characteristics of breast cancers. Methods Between January and August 2017, 274 consecutive breast cancer patients (mean age, 53.5 years; range, 25–80 years) who underwent ultrafast MRI and subsequent surgery were included for analysis. Ultrafast MRI scans were acquired using TWIST-VIBE or 4D TRAK-3D TFE sequences. TTE and maximum slope (MS) were derived from the ultrafast MRI. The repeated measures ANOVA, Mann–Whitney U test and Kruskal–Wallis H test were performed to compare the median TTE, MS and SER according to histologic type, histologic grade, ER/PR/HER2 positivity, level of Ki-67 and tumour subtype. For TTE calculation, intraclass correlation coefficient (ICC) was used to evaluate interobserver variability. Results The median TTE of invasive cancers was shorter than that of in situ cancers ( p