Evaluation of diffusion-weighted magnetic resonance imaging and contrast-enhanced harmonic ultrasonography in detection and location of prostate transition-zone cancer.

This retrospective study was designed to evaluate the value of contrast-enhanced harmonic ultrasonography (CEHU), diffusion-weighted magnetic resonance imaging (DW-MRI) and CEHU plus DW-MRI for the diagnosis of prostate transition-zone (TZ) cancer. In total, 31 TZ cancers in 28 patients and 25 peripheral zone (PZ) cancers in 21 patients without a TZ cancer were evaluated. All patients underwent DW-MRI and CEHU followed by radical prostatectomy. Predictors for the diagnosis of prostate cancer were evaluated in three protocols (CEHU, DW-MRI, CEHU plus DW-MRI). Statistical analysis of the differences between these protocols and receiver operating characteristic (ROC) curve analysis were carried out. CEHU plus DW-MRI had a significantly higher sensitivity, accuracy and negative-predictive value (90.3%, 73.2% and 81.3%, respectively) for TZ cancer than either method alone. The area under the ROC curve values were 0.659, 0.679 and 0.712 for CEHU, DW-MRI, and CEHU plus DW-MRI, respectively. In conclusion, CEHU plus DW-MRI might be a useful protocol for the detection and location of TZ cancer.