Histogram analysis from stretched exponential model on diffusion-weighted imaging: evaluation of clinically significant prostate cancer

Abstract

Objective: To evaluate the usefulness of histogram analysis of stretched exponential model (SEM) on diffusion-weighted imaging in evaluating clinically significant prostate cancer (CSC). Methods: A total of 85 patients with prostate cancer underwent 3 T multiparametric MRI, followed by radical prostatectomy. Histogram parameters of the tumor from the SEM [distributed diffusion coefficient (DDC) and α] and the monoexponential model [MEM; apparent diffusion coefficient (ADC)] were evaluated. The associations between parameters and Gleason score or Prostate Imaging Reporting and Data System v. 2 were evaluated. The area under the receiver operating characteristics curve was calculated to evaluate diagnostic performance of parameters in predicting CSC. Results: The values of histogram parameters of DDC and ADC were significantly lower in patients with CSC than in patients without CSC (p < 0.05), except for skewness and kurtosis. The value of the 25th percentile of α was significantly lower in patients with CSC than in patients without CSC (p = 0.014). Histogram parameters of ADC and DDC had significant weak to moderate negative associations with Gleason score or Prostate Imaging Reporting and Data System v. 2 (p < 0.001), except for skewness and kurtosis. For predicting CSC, the area under the curves of mean ADC (0.856), 50th percentile DDC (0.852), and 25th percentile α (0.707) yielded the highest values compared to other histogram parameters from each group. Conclusion: Histogram analysis of the SEM on diffusion-weighted imaging may be a useful quantitative tool for evaluating CSC. However, the SEM did not outperform the MEM. Advances in knowledge: Histogram parameters of SEM may be useful for evaluating CSC.

Sub-differentiation of PI-RADS 3 lesions in TZ by advanced diffusion-weighted imaging to aid the biopsy decision process

“…Several studies have found that csPCa has a lower D value and DDC value than non-csPCA and BPH. Moreover, D and DDC showed a negative relationship with the Gleason pattern (19, 25,34), which is in line with our results. These findings strongly suggest that parameters FA, MD, MK of DKI, parameter ADC, D of IVIM, and parameter D of the stretched exponential model could be potentially used to detect csPCa.…”

“…Our results showed that combining quantitative parameters FA, MD, and MK of DKI, parameter D of IVIM, and parameter DDC of the stretched exponential model could effectively identify PCa from PI-RADS 3 lesions. D value, DDC value and MD value of PCa (0.583×10 -3 mm/s, 0.662×10 -3 mm/s, 0.989×10 -3 mm/s) were significantly lower than that of BPH (0.778×10 -3 mm/s, 0.965×10 -3 mm/s, 1.219×10 -3 mm/ s), which is consistent with the results of previous studies (23)(24)(25). D, DDC, and MD all reflect the diffusion of water molecules in tissues.…”

Clinical value of minimum apparent diffusion coefficient for prediction of clinically significant prostate cancer in the transition zone

“…Specifically, suspicious lesions in the PZ with ADC values below 750-900 µm 2 /s are more likely to represent PC [3]. However, the reference ADC value for predicting PC in the transition zone (TZ) remains unclear [10][11][12][13][14].…”