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Purpose: To evaluate the role of Prostate Imaging Reporting and Data System v. 2 (PI-RADSv2) in triaging patients with prostate cancer according to Prostate Cancer Research International: Active Surveillance (PRIAS).Materials and Methods: Between January 2012 and December 2014, 456 patients with biopsy-proven cancer underwent multiparametric 3T magnetic resonance imaging (MRI) using T2 -weighted, diffusion-weighted, and dynamic contrast-enhanced MRI sequences, and then radical prostatectomy. Two radiologists independently reviewed MR images using PI-RADSv2. For AS, PRIAS required clinical stage Results: The sensitivity and specificity with PRIAS were 82.9% (68/82) and 70.9% (265/374), respectively. PI-RADSv2 decreased the sensitivity to 61% (50/82) to 80.5% (66/82), but increased the specificity to 77.8% (291/374) to 90.8% (340/374). The combination of PRIAS and PI-RDASv2 increased significantly the specificity to 89.6% (335/374) to 92.8% (347/374) (P < 0.001).Conclusion: PRIAS using multiparametric MRI can identify a greater number of insignificant cancers than PI-RADSv2. However, PI-RADSv2 helps detect many significant cancers that are misdiagnosed as insignificant cancer with PRIAS.Level Of Evidence: 3 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;45:1753-1759. [ABSTRACT FROM AUTHOR] more...

Background The purpose of this study was to evaluate the prostate cancer yield rate of targeted transrectal ultrasound (TRUS)-guided biopsy with cognitive magnetic resonance imaging (MRI) registration without concurrent systematic biopsy in patients with previous negative systematic TRUS-guided biopsy results and persistently elevated prostate-specific antigen (PSA) levels. Methods In this prospective study conducted from August 2013 to January 2015, patients with at least one previous negative systematic TRUS-guided biopsy and persistently high PSA (≥4 ng/mL) levels were referred for multiparametric MRI (mpMRI). Those patients with suspicious findings on mpMRI received a subsequent cognitive MRI-TRUS fusion biopsy. The cancer-detection rate, tumor location, and Gleason score were confirmed, and PSA-related data were compared between cancer-yield and noncancer-yield groups. Results In total, 48 patients were included in this study. MRI was designated to be four and five in 17 patients. Fifteen patients received a cognitive fusion-targeted biopsy, and prostate cancers were detected in 10 patients. The cancer-detection rate was 20.8% (10/48), and the positive-predictive value of MRI was 66.7%. No significant differences were observed in the PSA level, PSA velocity, or transitional zone volume between the cancer-yield and noncancer-yield groups; however, the corresponding difference in PSA transitional zone density was significant ( p = 0.025). Conclusion Cognitive MRI-TRUS fusion-targeted biopsy without concurrent systematic biopsy can detect significant prostate cancer in patients with previous negative systematic biopsy results and persistently elevated PSA levels. Noncancer-yield patients should undergo active surveillance and further follow-ups. [ABSTRACT FROM AUTHOR] more...

Objective: To retrospectively evaluate the diagnostic performance of single-phase dual-energy CT (DECT) with virtual non-contrast CT (VNCT) compared with three-phase CT urography (CTU) in patients with haematuria.Methods: A total of 296 patients underwent three-phase CTU (NCT at 120 kVp; nephrographic phase and excretory phase DECTs at 140 kVp and 80 kVp) owing to haematuria. Diagnostic performances of CT scans were compared for detecting urothelial tumours and urinary stones. Dose-length product (DLP) was compared in relation to single-phase DECT and three-phase CTU Dose-length product (DLP) was compared in relation to single-phase DECT and three-phase CTU.Results: Sensitivity and specificity for tumour were 95 % (19/20) and 98.9 % (273/276) on CTU, 95 % (19/20) and 98.2 % (271/276) on nephrographic phase DECT, and 90 % (18/20) and 98.2 % (271/276) on excretory phase DECT (P > 0.1). Of the 148 stones detected on NCT, 108 (73 %) and 100 (67.6 %) were detected on nephrographic phase and excretory phase VNCTs, respectively. The mean size of stones undetected on nephrographic and excretory VNCTs was measured as 1.5 ± 0.5 mm and 1.6 ± 0.6 mm, respectively. The mean DLPs of three-phase CTU, nephrographic phase DECT and excretory phase DECT were 1076 ± 248 mGy · cm, 410 ± 98 mGy · cm, and 360 ± 87 mGy · cm, respectively (P < 0.001).Conclusions: Single-phase DECT has a potential to replace three-phase CTU for detecting tumours with a lower radiation dose.Key Points: • Single-phase DECT with virtual NCT may replace three-phase CTU for detecting tumours. • Virtual NCT cannot replace NCT for detecting small urinary stones. • Single-phase DECT may reduce the radiation dose by 62-67 % compared to three-phase CTU. • Nephrographic phase DECT is superior to excretory phase DECT for assessing haematuria. [ABSTRACT FROM AUTHOR] more...

Objective: To investigate the value of post-treatment diffusion-weighted imaging (DWI) for predicting disease progression following concurrent chemoradiotherapy (CCRT) for cervical cancer.Methods: This retrospective study included 100 consecutive patients with locally advanced cervical cancer who underwent T2-weighted imaging (T2WI) and DWI 1 month after completing CCRT. The presence of residual tumour was independently determined on T2WI and T2WI plus DWI. The imaging findings were compared regarding prediction of disease progression.Results: Disease progressed in 24 patients during follow-up. Forty-one and 22 patients were determined as having residual tumour on T2WI and T2WI plus DWI, respectively. Regarding prediction of disease progression, positive predictive values of imaging findings on T2WI and T2WI plus DWI were 32.7 % and 54.4 %, respectively, 1 year after treatment (P = 0.004), 37.2 % and 73.0 %, respectively, 2 years after treatment (P < 0.001), and 39.3 % and 72.7 %, respectively, 3 years after treatment (P = 0.001). Multivariate Cox regression analysis revealed that the presence of residual tumour on T2WI plus DWI was the independent predictor of disease progression (hazard ratio = 6.34, P < 0.001).Conclusion: Post-treatment DWI offers an incremental value to T2WI in predicting disease progression after CCRT of cervical cancer.Key Points: • T2WI alone has limited prognostic value after CCRT of cervical cancer. • Adding DWI to T2WI improves prediction of disease progression after CCRT. • Residual tumour on post-treatment T2WI plus DWI is associated with disease progression. [ABSTRACT FROM AUTHOR] more...

Objective: To investigate whether gadolinium-based contrast agent (GBCA) administration significantly affects diffusion-weighted imaging (DWI) at 3 T in the evaluation of prostate cancer and benign tissue.Method: Thirty-four consecutive patients with surgically proven prostate cancer underwent preoperative DWI at 3 T before and after GBCA administration. Exponential apparent diffusion coefficient (EADC) and ADC maps were developed from DWI data. The ADC and EADC values pre- and post-contrast were measured in the cancer and benign tissue, respectively. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were evaluated on pre- and post-contrast DWI.Results: The ADC and EADC values of the cancer and benign transition zone were not significantly different between pre- and post-contrast, respectively (P > 0.05), while those in the benign peripheral zone were significantly different (P = 0.030 and 0.037, respectively). In all tissues, the SNRs and CNRs of the DWI, ADC map and EADC map were not significantly different between pre- and post-contrast (P > 0.05). Between pre- and post-contrast, ADC and EADC values showed excellent agreement (intraclass correlation coefficient ≥ 0.894) and variability of ≤3.2 %.Conclusion: Prostate 3 T-DWI after GBCA administration may be used without a significant difference in SNR or CNR, with minimal variability of the cancer ADC and EADC values.Key Points: • ADCs and EADCs have excellent agreement before and after gadobutrol administration. • SNRs of prostate DWI are similar before and after gadobutrol administration. • CNRs of cancers are similar between pre- and post-contrast DWI. [ABSTRACT FROM AUTHOR] more...

Background: Transanal total mesorectal excision (taTME) is expected to provide benefits in the removal of the complete mesorectum for low rectal lesions, and several clinical studies regarding this technique have been reported. However, a transanal platform has not yet been standardized, and diverse transanal endoluminal surgery access devices have been used, based on individual surgeon preferences. In the present study, we performed laparoscopy-assisted taTME in cadavers and compared the characteristics of four different platforms.Methods: Between January 2013 and April 2015, laparoscopy-assisted taTME was performed on six fresh cadavers. Flexible [SILS™ Port (Covidien), GelPOINT(®) Path Transanal Access Platform (Applied Medical)] and rigid [TEO(®) (Karl Storz Endoskope), TEM (Richard Wolf)] transanal access platforms were used on three cadavers each.Results: All cadavers were male, with a mean age of 69.2 (range 57-86) years. The mean operation time was 146.3 (range 140-155) min with flexible platforms and 206.7 (range 150-260) min with rigid platforms. The mean specimen length was 23 (range 18-26) cm. Complete or nearly complete mesorectal specimens were obtained in all cases, except for one case using the TEM platform. Flexible platforms (SILS and GelPOINT) provided a short set-up time, relatively atraumatic retraction, and easy application of familiar laparoscopic instruments; a narrow operative field was its limitation. The rigid platforms (TEO and TEM) enabled larger and more stable operative fields and space than did the SILS platform, but they were limited by a narrow view, prolonged set-up time, rigidity, and long channels relative to the short distance from the anus to the rectal closure site.Conclusion: In this preliminary study, laparoscopy-assisted taTME was a feasible and safe procedure using both rigid and soft platforms, despite some limitations of each platform. [ABSTRACT FROM AUTHOR] more...