Deep‐learning prostate cancer detection and segmentation on biparametric versus multiparametric magnetic resonance imaging: Added value of dynamic contrast‐enhanced imaging

Objectives To develop diagnostic algorithms of multisequence prostate magnetic resonance imaging for cancer detection and segmentation using deep learning and explore values of dynamic contrast‐enhanced imaging in multiparametric imaging, compared with biparametric imaging. Methods We collected 3227 multiparametric imaging sets from 332 patients, including 218 cancer patients (291 biopsy‐proven foci) and 114 noncancer patients. Diagnostic algorithms of T2‐weighted, T2‐weighted plus dynamic contrast‐enhanced, biparametric, and multiparametric imaging were built using 2578 sets, and their performance for clinically significant cancer was evaluated using 649 sets. Results Biparametric and multiparametric imaging had following region‐based performance: sensitivity of 71.9% and 74.8% ( p = 0.394) and positive predictive value of 61.3% and 74.8% ( p = 0.013), respectively. In side‐specific analyses of cancer images, the specificity was 72.6% and 89.5% ( p < 0.001) and the negative predictive value was 78.9% and 83.5% ( p = 0.364), respectively. False‐negative cancer on multiparametric imaging was smaller ( p = 0.002) and more dominant with grade group ≤2 ( p = 0.028) than true positive foci. In the peripheral zone, false‐positive regions on biparametric imaging turned out to be true negative on multiparametric imaging more frequently compared with the transition zone (78.3% vs. 47.2%, p = 0.018). In contrast, T2‐weighted plus dynamic contrast‐enhanced imaging had lower specificity than T2‐weighted imaging (41.1% vs. 51.6%, p = 0.042). Conclusions When using deep learning, multiparametric imaging provides superior performance to biparametric imaging in the specificity and positive predictive value, especially in the peripheral zone. Dynamic contrast‐enhanced imaging helps reduce overdiagnosis in multiparametric imaging.