Abbreviated MRI protocol in breast cancer diagnosis: comparison with the full diagnostic protocol
Abstract
Full diagnostic protocol breast magnetic resonance imaging (FDP-MRI) provides good sensitivity but is constrained by long acquisition times and high costs. Abbreviated magnetic resonance imaging (AMRI) protocols have been proposed to overcome these limitations. This study aimed to develop and validate AMRI protocols and evaluate their diagnostic performance against FDP-MRI in breast cancer diagnosis. This retrospective study included 220 women (mean age, 51.4 ± 11.3 years) with ultrasonography-detected lesions, who underwent FDP-MRI from September 2021 to September 2024. Three AMRI protocols were derived: non-contrast (NC)-AMRI: T2-weighted imaging + diffusion-weighted imaging (DWI); dynamic contrast-enhanced (DCE)-AMRI A: first post-contrast subtracted (FAST) + maximum-intensity projection (MIP); and DCE-AMRI B: FAST + MIP + DWI. Two radiologists, blinded to pathology, independently interpreted all protocols and classified lesions using the Breast Imaging Reporting and Data System (category ≥ 4 considered positive). Diagnostic performance was compared using Cochran’s Q with post-hoc McNemar tests. Receiver operating characteristic curve and areas under the curve (AUCs) were analysed by DeLong’s test. Acquisition times differed significantly between the protocols (FDP-MRI: 16 min 5 s; NC-AMRI: 4 min 20 s; DCE-AMRI A: 2 min 41 s; DCE-AMRI B: 6 min 35 s; all p < 0.001). DCE-AMRI A showed the highest sensitivity (85.26%) but the lowest specificity (74.49%). DCE-AMRI B achieved balanced performance with a sensitivity of 83.60% (95% confidence interval, CI: 75.82-89.69) and specificity of 85.71% (95% CI: 77.19-91.96), which was comparable to FDP-MRI (84.42% and 90.81%, respectively; all p > 0.05). DCE-AMRI B and FDP-MRI showed equivalent AUCs (0.847 vs. 0.876; p = 0.085). The DCE-AMRI B protocol represents a time-efficient alternative to FDP-MRI, particularly suitable for women with limited tolerance to prolonged prone positioning, offering improved clinical accessibility and workflow efficiency without compromising diagnostic performance.