Early-phase semi-quantitative analysis versus full time-course quantitative modeling of ultrafast dynamic contrast-enhanced MRI for breast cancer diagnosis, molecular subtyping, and treatment response prediction.

OBJECTIVES

To evaluate the performance of semi-quantitative analysis versus quantitative pharmacokinetic analysis applied to ultrafast dynamic contrast-enhanced (UF-DCE) MRI in: (1) differentiating benign from malignant breast lesions, (2) molecular subtyping, and (3) predicting pathologic complete response (pCR) following neoadjuvant chemotherapy.

MATERIALS AND

METHODS

This prospective noninferiority study enrolled 339 consecutive participants with suspected breast lesions between September 2022 and February 2024. All underwent breast DCE MRI with a temporal resolution of 4.5 s, totaling 100 phases. Using the initial 30 phases (early-phase UF-DCE), five semi-quantitative parameters were calculated: wash-in slope (WIS), time-to-peak, bolus arrival time, peak enhancement intensity (PEI), and initial area under the curve in 60 s. Furthermore, three quantitative parameters: volume transfer constant, rate constant (kep), and extravascular extracellular space volume, were derived from the 100-phase dataset (full time-course UF-DCE). Diagnostic performance was assessed using areas under the curve (AUC) and the DeLong test, with Pearson analysis evaluating the correlation between semi-quantitative and quantitative parameters.

RESULTS

All semi-quantitative and quantitative parameters showed differences between benign and malignant breast lesions (p < 0.001). Semi-quantitative WIS demonstrated noninferior diagnostic performance to quantitative kep in differentiating benign from malignant lesions (AUC: 0.93 vs 0.92; ∆AUC = 0.02, p = 0.35). However, neither approach effectively distinguished molecular subtypes or predicted pCR (p > 0.05). Strong correlations were observed in PEI and Ktrans (r = 0.75, p < 0.001).

CONCLUSION

Semi-quantitative analysis of early-phase UF-DCE exhibits noninferior performance to quantitative analysis of full time-course UF-DCE MRI for distinguishing benign from malignant breast lesions. Both analytical approaches showed limited utility in molecular subtyping and pCR prediction.

CRITICAL RELEVANCE STATEMENT: Early-phase UF-DCE MRI provides a cost-effective alternative to full time-course UF-DCE MRI for differentiating benign and malignant breast lesions, demonstrating noninferior diagnostic performance with reduced scan time and no need for pharmacokinetic modeling.

KEY POINTS: Systematic comparison of early-phase UF-DCE and full time-course UF-DCE MRI for diagnosis, subtyping, and response prediction in a single breast cancer cohort remains limited. Early-phase UF-DCE MRI demonstrated noninferior diagnostic performance to full time-course UF-DCE MRI in differentiating benign and malignant breast lesions. Early-phase UF-DCE MRI is a time-efficient alternative to full time-course UF-DCE MRI for clinical implementation.