Diagnostic accuracy of biparametric vs. multiparametric MRI for clinically significant prostate cancer

Multiparametric magnetic resonance imaging (MRI) is the most widely used approach for prostate MRI. While biparametric MRI (BP-MRI) involves shorter acquisition time and decreased cost, its diagnostic accuracy compared to multiparametric MRI (MP-MRI) is not well known. We aim to compare the detection of clinically significant prostate cancer with BP-MRI and MP-MRI prior to biopsy.

We retrospectively analyzed men who underwent BP-MRI or MP-MRI between January 2019 and December 2022, interpreted by a single expert radiologist. All patients underwent systematic and targeted transperineal prostate biopsy. Diagnostic performance was compared using Receiver operating characteristic curves, test performance parameters, and assessed net benefit with decision curve analysis, using biopsy with Grade Group ≥ 2 disease as the reference standard.

Among 310 patients (192 MP-MRI, 118 BP-MRI), suspicious lesions were identified in 63% vs. 47%, respectively. Area under the curve values were 0.81 for MP-MRI and 0.88 for BP-MRI (p = 0.4). At PI-RADS ≥ 4, BP-MRI sensitivity/specificity were 71%/79% vs. 79%/55% for MP-MRI. At PI-RADS ≥ 3, sensitivities were similar but specificities were lower for both. Decision curve analysis showed similar net benefit for both protocols across clinically relevant thresholds. In multivariable analysis adjusting for age and PI-RADS, MRI type was not associated with clinically significant cancer detection (OR 0.88, 95% CI 0.53-1.45).

Biparametric and multiparametric MRI protocols demonstrate comparable accuracy in the detection of clinically significant prostate cancer, suggesting that dynamic contrast enhancement offers limited clinical benefit. Biparametric MRI should be considered the standard for pre-biopsy imaging in patients with suspected prostate cancer.