Abbreviated breast MRI combining FAST protocol and high temporal resolution (HTR) dynamic contrast enhanced (DCE) sequence

Abstract

Purpose: We evaluated the diagnostic value of a high temporal resolution (HTR) dynamic contrast enhanced (DCE) sequence added to a FAST protocol.

Materials and methods: 120 women (mean age = 55 years (28-88)) who underwent breast MRI between July 2016 and March 2017 and in whom a biopsy was performed (i.e., gold standard) (n = 179: 69 benign, 7 borderline and 103 malignant lesions) were retrospectively and consecutively included. Two readers classified lesions according to the Breast Imaging-Reporting and Data System (BI-RADS) by reading: a FAST protocol (T1W, T2W, T1W-fat saturated 2 min after injection) and then a FULL standard protocol. Independently they determined if lesions were visible and when (Time To Enhancement (TTE)) on the HTR-DCE sequence. An Abbreviated protocol was then built using data from the HTR-DCE sequence added to the FAST protocol.

Results: All lesions were visible with the FAST protocol. 171/179 (95.5%) lesions were detected by reading theHTR-DCE sequence. There were a higher number of cancers rated BI-RADS 3 (PPV of malignancy of 27.6% (8/29) in FAST versus 18.7% (3/16) FULL protocol). An early enhancement on the HTR-DCE sequence (TTE < 31 s) was associated with malignancy with an OR 5.6 (CI 95%: 3.3-20.4) (p < 0.0001). Adding a TTE < 31 s to FAST analysis (AUROC = 0.826) significantly improved lesion characterization with a diagnostic gain of 10.6% (19/179) lesions correctly reclassified (p = 0.0034) compared to FAST protocol; with shorter acquisition time (7 min 48 s versus 13 min 54 s).

Conclusion: Adding an HTR-DCE sequence to a FAST protocol increases diagnostic performance reaching that of the FULL protocol while reducing acquisition time.

Keywords: Breast; Cancer; FAST; High temporal resolution DCE sequence; MRI.