Xiangde Min

Correlation of gleason scores with magnetic resonance diffusion tensor imaging in peripheral zone prostate cancer.

To investigate tumor aggressiveness in peripheral zone prostate cancer (PCa) by correlating Gleason score (GS) with diffusion tensor imaging (DTI) from multiparametric magnetic resonance imaging (MRI) at 3.0 Tesla (T).

Comparison of field-of-view (FOV) optimized and constrained undistorted single shot (FOCUS) with conventional DWI for the evaluation of prostate cancer

OBJECTIVES Qualitative and quantitative comparison of the application value of diffusion-weighted imaging (DWI) magnetic resonance imaging based on field-of-view (FOV) optimized and constrained undistorted single shot (FOCUS) with the standard single-shot echo-planar imaging (ss-EPI) in patients with prostate cancer. METHODS A total of 28 patients with 33 prostate cancers underwent ss-EPI and FOCUS DWI. Two independent readers assessed image studies. RESULTS Image qualities of FOCUS were rated superior to ss-EPI (P<.001). The mean apparent diffusion coefficient value of 33 cancers was 974.030×10(-6)mm(2)/s and 941.727×10(-6)mm(2)/s, respectively, and the difference was statistically significant (t=2.579, P=.015). CONCLUSIONS FOCUS as a high-resolution DWI technique has potential clinical utility.

Prostate Cancer Detection with Multiparametric Magnetic Resonance Imaging: Prostate Imaging Reporting and Data System Version 1 versus Version 2

Background: Prostate Imaging Reporting and Data System (PI-RADS) is a globally acceptable standardization for multiparametric magnetic resonance imaging (mp-MRI) in prostate cancer (PCa) diagnosis. The American College of Radiology revised the PI-RADS to address the limitations of version 1 in December 2014. This study aimed to determine whether the PI-RADS version 2 (PI-RADS v2) scoring system improves the diagnostic accuracy of mp-MRI of the prostate compared with PI-RADS v1. Methods: This retrospective study was approved by the institutional review board. A total of 401 consecutive patients, with clinically suspicious PCa undergoing 3.0 T mp-MRI (T2-weighted imaging + diffusion-weighted imaging + DCE) before transrectal ultrasound-guided biopsy between June 2013 and July 2015, were included in the study. All patients were scored using the 5-point PI-RADS scoring system based on either PI-RADS v1 or v2. Receiver operating characteristics were calculated for statistical analysis. Sensitivity, specificity, and diagnostic accuracy were compared using McNemars test. Results: PCa was present in 150 of 401 (37.41%) patients. When we pooled data from both peripheral zone (PZ) and transition zone (TZ), the areas under the curve were 0.889 for PI-RADS v1 and 0.942 for v2 (P = 0.0001). Maximal accuracy was achieved with a score threshold of 4. At this threshold, in the PZ, similar sensitivity, specificity, and accuracy were achieved with v1 and v2 (all P > 0.05). In the TZ, sensitivity was higher for v2 than for v1 (96.36% vs. 76.36%, P = 0.003), specificity was similar for v2 and v1 (90.24% vs. 84.15%, P = 0.227), and accuracy was higher for v2 than for v1 (92.70% vs. 81.02%, P = 0.002). Conclusions: Both v1 and v2 showed good diagnostic performance for the detection of PCa. However, in the TZ, the performance was better with v2 than with v1.

Evaluation of different mathematical models and different b-value ranges of diffusion-weighted imaging in peripheral zone prostate cancer detection using b-value up to 4500 s/mm2

Objectives To evaluate the diagnostic performance of different mathematical models and different b-value ranges of diffusion-weighted imaging (DWI) in peripheral zone prostate cancer (PZ PCa) detection. Methods Fifty-six patients with histologically proven PZ PCa who underwent DWI-magnetic resonance imaging (MRI) using 21 b-values (0–4500 s/mm2) were included. The mean signal intensities of the regions of interest (ROIs) placed in benign PZs and cancerous tissues on DWI images were fitted using mono-exponential, bi-exponential, stretched-exponential, and kurtosis models. The b-values were divided into four ranges: 0–1000, 0–2000, 0–3200, and 0–4500 s/mm2, grouped as A, B, C, and D, respectively. ADC, , D*, f, DDC, α, Dapp, and Kapp were estimated for each group. The adjusted coefficient of determination (R2) was calculated to measure goodness-of-fit. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic performance of the parameters. Results All parameters except D* showed significant differences between cancerous tissues and benign PZs in each group. The area under the curve values (AUCs) of ADC were comparable in groups C and D (p = 0.980) and were significantly higher than those in groups A and B (p< 0.05 for all). The AUCs of ADC and Kapp in groups B and C were similar (p = 0.07 and p = 0.954), and were significantly higher than the other parameters (p< 0.001 for all). The AUCs of ADC in group D was slightly higher than Kapp (p = 0.002), and both were significantly higher than the other parameters (p< 0.001 for all). Conclusions ADC derived from conventional mono-exponential high b-value (3200 s/mm2) models is an optimal parameter for PZ PCa detection.

Effects of Echo Time on IVIM Quantification of the Normal Prostate

The two-compartment intravoxel incoherent motion (IVIM) theory assumes that the transverse relaxation time is the same in both compartments. However, blood and tissue have different T2 values, and echo time (TE) may thus have an effect on the quantitative parameters of IVIM. The purpose of this study was to investigate the effects of TE on IVIM-DWI-derived parameters of the prostate. In total, 17 healthy volunteers underwent two repeat examinations. IVIM-DWI data were scanned 6 times with variable TE values of 60, 70, 80, 90, 100, and 120 ms. The ADC of a mono-exponential model and the D, D*, and f parameters of the IVIM model were calculated separately for each TE. Repeat measures were assessed by calculating the coefficient of variation and Bland-Altman limits of agreement for each parameter. Spearman’s rho test was used to analyse relationships between IVIM indices and TE. Our results showed that TE had an effect on IVIM quantification, which should be kept constant in the examination protocol at each individual institution. Alternatively, an extended IVIM could be used to eliminate the effect of the TE value on the quantitative parameters of IVIM. This may be helpful for guiding clinical research, especially for longitudinal studies.

Characterization of testicular germ cell tumors: Whole-lesion histogram analysis of the apparent diffusion coefficient at 3T

PURPOSE To assess the values of parameters derived from whole-lesion histograms of the apparent diffusion coefficient (ADC) at 3T for the characterization of testicular germ cell tumors (TGCTs). MATERIALS AND METHODS A total of 24 men with TGCTs underwent 3T diffusion-weighted imaging. Fourteen tumors were pathologically confirmed as seminomas, and ten tumors were pathologically confirmed as nonseminomas. Whole-lesion histogram analysis of the ADC values was performed. A Mann-Whitney U test was employed to compare the differences in ADC histogram parameters between seminomas and nonseminomas. Receiver operating characteristic analysis was used to identify the cutoff values for each parameter for differentiating seminomas from nonseminomas; furthermore, the area under the curve (AUC) was calculated to evaluate the diagnostic accuracy. RESULTS The median of 10th, 25th, 50th, 75th, and 90th percentiles and mean, minimum and maximum ADC values were all significantly reduced for seminomas compared with nonseminomas (p<0.05 for all). In contrast, the median of kurtosis and skewness of ADC values of seminomas were both significantly increased compared with those of nonseminomas (p=0.003 and 0.001, respectively). For differentiating nonseminomas from seminomas, the 10th percentile ADC yielded the highest AUC with a sensitivity and specificity of 100% and 92.86%, respectively. CONCLUSION Whole-lesion histogram analysis of ADCs might be used for preoperative characterization of TGCTs.

Abernethy Malformation Type II and Concurrent Nodular Hyperplasia in a Rare Female Case

Background Abernethy malformation is a rare splanchnic vascular abnormality characterizing extrahepatic abnormal shunts that is classified into types I and II. Abernethy malformation type I has a female predilection and is associated with a variety of concurrent hepatic benign or malignant tumours while type II with concurrent tumours is very rare in females. Case Report We report a rare female case of Abernethy malformation type II with concurrent occupying lesion in the right liver, which was successfully transplanted; the occupying lesion was pathologically proven to be nodular hyperplasia. Conclusion This case might provide further knowledge regarding Abernethy malformation. On imaging, the anatomy of portal vein should be carefully investigated to categorize Abernethy malformation, and a wide variety of differential diagnosis of concurrent occupying lesions should be taken into account.

Benign prostatic hyperplasia after prostatic arterial embolization in a canine model: A 3T multiparametric MRI and whole-mount step-section pathology correlated longitudinal study

To explore the morphological and functional characteristics of prostatic arterial embolization (PAE) in a canine model of benign prostatic hyperplasia (BPH) with 3T multiparametric magnetic resonance imaging (mp‐MRI) and whole‐mount step‐section pathology correlation.

MRI feature analysis of uncommon prostatic malignant tumors

transurethral resection of the prostate in one patient, and open surgery in three patients. The final pathological diagnoses were embryonal rhabdomyosarcoma (RMS) in two patients, prostatic stromal sarcoma (PSS) in four, mesenchymal tumors not-otherwise-specified in four, small cell carcinoma (SCC) in three, and lymphoma in two. All the patients underwent conventional MRI including T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI), nine patients underwent diffusion-weighted imaging (DWI), and ten patients underwent dynamic contrast-enhanced (DCE) MRI. The clinical characteristics and MRI findings are shown in Table 1. The detailed clinical, immunohistochemical, and MRI information are shown in Supplementary Table 1–3. Tumors were round (n = 3), lobular (n = 6), and irregular (n = 6). Eleven tumors occupied the entire prostate, with loss of the normal zonal anatomy on T2-weighted images. Four tumors occupied the majority of the prostate. Among the nine patients who had DWI examinations, all tumors showed high signal and the apparent diffusion coefficient value was relatively low. A typical case of embryonal rhabdomyosarcoma is shown in Figure 1. The tumor presented with a well-defined T2 low signal pseudocapsule with internal cystic degeneration, bleeding, large necrotic areas and exerted a significant mass effect on bladder and rectum. For the ten prostatic malignant mesenchymal tumors, tumors had low signals mixed with patchy high signals (n = 5) and were isointense (n = 5) on T1WI. Most prostate sarcomas had heterogeneous signal intensity on T2WI, which was consistent with multiple cysts (8/10), hemorrhagic necrosis (7/10) as well as marked heterogeneous enhancement (6/6) after the administration of contrast agents. Most of the prostate sarcomas (9/10) presented with a well-defined T2 low signal pseudocapsule and exerted a significant mass effect on adjacent structures, such as bladder (n = 5) and rectum (n = 5). There was evidence of adjacent invasion of the seminal vesicle (n = 8), bladder (n = 2), and rectum (n = 3). There was evidence of distant metastatic spread (lung metastasis in two cases and liver metastasis in one case). For the three small-cell carcinomas, T2WI showed a large heterogeneous prostatic mass and the prostate capsule was incomplete. The lesions were isointense on T1WI and mildly hyperintense on T2WI. The lesions showed mild or moderate heterogeneous enhancement after the administration of a contrast agent. Some cases showed invasion of adjacent structures, which showed involvement of the seminal vesicle (n = 3), bladder (n = 3), and rectum (n = 2). Pelvis lymph node metastasis was present in one case. There was evidence of distant metastasis in one (liver) case and two (bone) cases. For the two B-cell non-Hodgkin lymphomas, one case was predominantly in the prostate Dear Editor, Most prostatic neoplasms are epithelial in origin. Non-epithelial prostatic neoplasms are quite rare, but they cover a broad array of types that include neuroendocrine tumors, mesenchymal tumors, hematolymphoid tumors, miscellaneous tumors, etc.1,2 Unlike prostate cancer, there is no specific serum marker for non-epithelial prostatic neoplasms at present, and the majority of patients present with a large pelvic mass and compressive symptoms of dysuria or abdominal pain. Imaging plays an important role in the investigation of prostate masses, although transrectal ultrasound-guided prostate biopsy remains the gold standard for diagnosis. Magnetic resonance imaging (MRI) contributes to determining the site of origin of the tumor, local extent, and signal characteristics owing to its high soft-tissue contrast resolution. Many studies have demonstrated that MRI characteristics can help predict histological types of tumors, which can guide clinical treatment.3–5 As there is a low morbidity rate for uncommon prostatic neoplasms, MRI features have rarely been described in the literature and they are mainly reported as case reports.6–8 In this letter, we retrospectively reviewed the MRI features of 15 cases of uncommon prostatic malignant tumors, which, to our knowledge, is the largest number of these tumors reported to assess MRI features. As accurate diagnosis is critical for appropriate clinical workup and management, the aim of this study was to explore some salient MRI characteristics of uncommon prostatic malignant tumors to improve understanding and facilitate the differential diagnosis. This retrospective study was approved by Tongji Hospital, Tongji Medical College, Huzhong University of Science and Technology Institutional Review Board. We collected the clinical data of 15 cases of uncommon prostatic tumor patients from January 1, 2011, to December 31, 2015, in Tongji Hospital. And informed consents were obtained from all patients. The age range was from 22 years to 69 years, with a median age of 46 years. Nine cases presented with dysuria, two cases had lower abdominal pain, two cases were accidentally discovered on routine physical examination, one case had dyschezia as well as fresh blood in the feces, and one case had waist pain as well as perineal pain. The median value of the serum prostate-specific antigen (PSA) was 1.412 (range: 0.435–126.634) ng ml−1. The pathological study was performed via transrectal ultrasound-guided biopsy in 11 patients, Open Access