What benefit can be obtained from magnetic resonance imaging diagnosis with artificial intelligence in prostate cancer compared with clinical assessments?

The present study aimed to explore the potential of artificial intelligence(AI)methodology based on magnetic resonance(MR)images to aid in the management of prostate cancer(PCa).To this end,we reviewed and summarized the studies comparing the diagnostic and predictive performance for PCa between AI and common clinical assessment methods based on MR images and/or clinical characteristics,thereby investigating whether AI methods are generally superior to common clinical assessment methods for the diagnosis and prediction fields of PCa.First,we found that,in the included studies of the present study,AI methods were generally equal to or better than the clinical assessment methods for the risk assessment of PCa,such as risk stratification of prostate lesions and the prediction of therapeutic outcomes or PCa progression.In particular,for the diagnosis of clinically significant PCa,the AI methods achieved a higher summary receiver operator characteristic curve(SROC-AUC)than that of the clinical assessment methods(0.87 vs.0.82).For the prediction of adverse pathology,the AI methods also achieved a higher SROC-AUC than that of the clinical assessment methods(0.86 vs.0.75).Second,as revealed by the radiomics quality score(RQS),the studies included in the present study presented a relatively high total average RQS of 15.2(11.0–20.0).Further,the scores of the individual RQS elements implied that the AI models in these studies were constructed with relatively perfect and standard radiomics processes,but the exact generalizability and clinical practicality of the AI models should be further validated using higher levels of evidence,such as prospective studies and open-testing datasets.

Quantitative magnetic resonance imaging in prostate cancer:A review of current technology

Prostate cancer(PCa)imaging forms an important part of PCa clinical management.Magnetic resonance imaging is the modality of choice for prostate imaging.Most of the current imaging assessment is qualitative i.e.,based on visual inspection and thus subjected to inter-observer disagreement.Quantitative imaging is better than qualitative assessment as it is more objective,and standardized,thus improving interobserver agreement.Apart from detecting PCa,few quantitative parameters may have potential to predict disease aggressiveness,and thus can be used for prognosis and deciding the course of management.There are various magnetic resonance imaging-based quantitative parameters and few of them are already part of PIRADS v.2.1.However,there are many other parameters that are under study and need further validation by rigorous multicenter studies before recommending them for routine clinical practice.This review intends to discuss the existing quantitative methods,recent developments,and novel techniques in detail.

From strength to precision: A systematic review exploring the clinical utility of 7-Tesla magnetic resonance imaging in abdominal imaging

BACKGROUND After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging(MRI)have demonstrated the feasibility as well as diagnostic capabilities of liver,kidney,and prostate MRI at 7-Tesla.However,the elevation of the field strength to 7-Tesla not only brought advantages to abdominal MRI but also presented considerable challenges and drawbacks,primarily stemming from heightened artifacts and limitations in Specific Absorption Rate,etc.Furthermore,evidence in the literature is relatively scarce concerning human studies in comparison to phantom/animal studies which necessitates an investigation into the evidence so far in humans and summarizing all relevant evidence.AIM To offer a comprehensive overview of current literature on clinical abdominal 7T MRI that emphasizes current trends,details relevant challenges,and provides a concise set of potential solutions.METHODS This systematic review adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.A PubMed search,utilizing Medical Subject Headings terms such as"7-Tesla"and organ-specific terms,was conducted for articles published between January 1,1985,and July 25,2023.Eligibility criteria included studies exploring 7T MRI for imaging human abdominal organs,encompassing various study types(in-vivo/ex-vivo,method development,reviews/meta-analyses).Exclusion criteria involved animal studies and those lacking extractable data.Study selection involved initial identification via title/abstract,followed by a full-text review by two researchers,with discrepancies resolved through discussion.Data extraction covered publication details,study design,population,sample size,7T MRI protocol,image characteristics,endpoints,and conclusions.RESULTS The systematic review included a total of 21 studies.The distribution of clinical 7T abdominal imaging studies revealed a predominant focus on the prostate(n=8),followed by the kidney(n=6)and the hepatobiliary system(n=5).Studies on these organs,and in the pancreas,demonstrated clear advantages at 7T.However,small bowel studies showed no significant improvements compared to traditional MRI at 1.5T.The majority of studies evaluated originated from Germany(n=10),followed by the Netherlands(n=5),the United States(n=5),Austria(n=2),the United Kingdom(n=1),and Italy(n=1).CONCLUSION Further increase of abdominal clinical MRI field strength to 7T demonstrated high imaging potential,yet also limitations mainly due to the inhomogeneous radiofrequency(RF)excitation field relative to lower field strengths.Hence,further optimization of dedicated RF coil elements and pulse sequences are expected to better optimize clinical imaging at high magnetic field strength.

Secondary rectal linitis plastica caused by prostatic adenocarcinoma-magnetic resonance imaging findings and dissemination pathways:A case report

BACKGROUND Secondary rectal linitis plastica(RLP)from prostatic adenocarcinoma is a rare and poorly understood form of metastatic spread,characterized by a desmoplastic response and concentric rectal wall infiltration with mucosal preservation.This complicates endoscopic diagnosis and can mimic gastrointestinal malignancies.This case series underscores the critical role of magnetic resonance imaging(MRI)in identifying the distinct imaging features of RLP and highlights the importance of considering this condition in the differential diagnosis of patients with a history of prostate cancer.CASE SUMMARY Three patients with secondary RLP due to prostatic adenocarcinoma presented with varied clinical features.The first patient,a 76-year-old man with advanced prostate cancer,had rectal pain and incontinence.MRI showed diffuse prostatic invasion and significant rectal wall thickening with a characteristic"target sign"pattern.The second,a 57-year-old asymptomatic man with elevated prostatespecific antigen levels and a history of prostate cancer exhibited rectoprostatic angle involvement and rectal wall thickening on MRI,with positron emission tomography/computed tomography PSMA confirming the prostatic origin of the metastatic spread.The third patient,an 80-year-old post-radical prostatectomy,presented with refractory constipation.MRI revealed a neoplastic mass infiltrating the rectal wall.In all cases,MRI consistently showed stratified thickening,concentric signal changes,restricted diffusion,and contrast enhancement,which were essential for diagnosing secondary RLP.Biopsies confirmed the prostatic origin of the neoplastic involvement in the rectum.CONCLUSION Recognizing MRI findings of secondary RLP is essential for accurate diagnosis and management in prostate cancer patients.

Computed tomography and magnetic resonance imaging findings of metastatic rectal linitis plastica from prostate cancer:A case report and review of literature

Linitis plastica is a rare condition showing circumferentially infiltrating intramural anaplastic carcinoma in a hollow viscus, resulting in a tissue thickening of the involved organ as constricted, inelastic, and rigid. While most secondary rectal linitis plastica(RLP) is caused by metastasis from stomach, breast, gallbladder, or bladder cancer, we report an extremely rare and unique case of secondary RLP due to prostate cancer with computed tomography(CT) and magnetic resonance imaging(MRI) findings, including diffusion weighted imaging(DWI). A 78-year-old man presented with approximately a 2-mo history of constipation and without cancer history. On sigmoidoscopy, there was a luminal narrowing and thickening of rectum with mucosa being grossly normal in its appearance. On contrast-enhanced CT,marked contrast enhancement with wall thickening of rectum was noted. On pelvic MRI, rectal wall thickening showed a target sign on both T2-weighted imaging and DWI. A diffuse infiltrative lesion was suspected in the prostate gland based on low signal intensity on T2-weighted imaging and restricted diffusion. A transanal full-thickness excisional biopsy revealed metastasis from a prostate adenocarcinoma invading the submucosa to the muscularis propria consistent with metastatic RLP. We would like to emphasize the CT and MRI findings of metastatic RLP due to prostate cancer.

Dynamic contrast-enhanced magnetic resonance imaging of prostate cancer: A review of current methods and applications

In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusion characteristics. Tumor angiogenesis is an essential process for tumor growth, proliferation, and metastasis. Malignant lesions demonstrate rapid extravasation of contrast from the intravascular space to the capillary bed due to leaky capillaries associated with tumor neovascularity. DCE-MRI has the potential to provide information regarding blood flow, areas of hypoperfusion, and variations in endothelial permeability and microvessel density to aid treatment selection, enable frequent monitoring during treatment and assess response to targeted therapy following treatment. This review will discuss the current status of DCE-MRI in cancer imaging, with a focus on its use in imaging prostate malignancies as well as weaknesses that limit its widespread clinical use. The latest techniques for quantification of DCE-MRI parameters will be reviewed and compared.

Updates in advanced diffusion-weighted magnetic resonance imaging techniques in the evaluation of prostate cancer

Diffusion-weighted magnetic resonance imaging(DWMRI) is considered part of the standard imaging protocol for the evaluation of patients with prostate cancer.It has been proven valuable as a functional tool for qualitative and quantitative analysis of prostate cancer beyond anatomical MRI sequences such as T2-weighted imaging. This review discusses ongoing controversies in DW-MRI acquisition, including the optimal number of b-values to be used for prostate DWI, and summarizes the current literature on the use of advanced DWMRI techniques. These include intravoxel incoherent motion imaging, which better accounts for the nonmono-exponential behavior of the apparent diffusion coefficient as a function of b-value and the influence of perfusion at low b-values. Another technique is diffusion kurtosis imaging(DKI). Metrics from DKI reflect excess kurtosis of tissues, representing its deviation from Gaussian diffusion behavior. Preliminary results suggest that DKI findings may have more value than findings from conventional DW-MRI for the assessment of prostate cancer.

Targeted prostate biopsy： value of multiparametric magnetic resonance imaging in detection of localized cancer

Prostate cancer is the second most common cancer in men, with 1.1 million new cases worldwide reported by the World Health Organization in one recent year. Transrectal ultrasound （TRUS）-guided biopsy has been used for the diagnosis of prostate cancer for over 2 decades, but the technique is usually blind to cancer location. Moreover, the false negative rate of TRUS biopsy has been reported to be as high as 47%. Multiparametric magnetic resonance imaging （mp-MRI） includes T1- and T2-weighted imaging as well as dynamic contrast-enhanced （DCE） and diffusion-weighted imaging （DWI）. mp-MRI is a major advance in the imaging of prostate cancer, enabling targeted biopsy of suspicious lesions. Evolving targeted biopsy techniquesmincluding direct in-bore biopsy, cognitive fusion and software-based MRI-ultrasound （MRI-US） fusion--have led to a several-fold improvement in cancer detection compared to the earlier method. Importantly, the detection of clinically significant cancers has been greatly facilitated by targeting, compared to systematic biopsy alone. Targeted biopsy via MRI-US fusion may dramatically alter the way prostate cancer is diagnosed and managed.

Magnetic resonance imaging for prostate cancer before radical and salvage radiotherapy: What radiation oncologists need to know

External beam radiotherapy(EBRT) is one of the principal curative treatments for patients with prostate cancer(PCa). Risk group classification is based on prostate-specific antigen(PSA) level, Gleason score, and T-stage. After risk group determination, the treatment volume and dose are defined and androgen deprivation therapy is prescribed, if appropriate. Traditionally, imaging has played only a minor role in T-staging due to the low diagnostic accuracy of conventional imaging strategies such as transrectal ultrasound, computed tomography, and morphologic magnetic resonance imaging(MRI). As a result, a notable percentage of tumours are understaged, leading to inappropriate and imprecise EBRT. The development of multiparametric MRI(mp MRI), an imaging technique that combines morphologic studies with functional diffusion-weighted sequences and dynamic contrastenhanced imaging, has revolutionized the diagnosis and management of PCa. As a result, mpM RI is now used in staging PCa prior to EBRT, with possible implications for both risk group classification and treatment decisionmaking for EBRT. mpM RI is also being used in salvageradiotherapy(SRT), the treatment of choice for patients who develop biochemical recurrence after radical prostatectomy. In the clinical context of biochemical relapse, it is essential to accurately determine the site of recurrence-pelvic(local, nodal, or bone) or distant-in order to select the optimal therapeutic management approach. Studies have demonstrated the value of mpM RI in detecting local recurrences-even in patients with low PSA levels(0.3-0.5 ng/m L)-and in diagnosing bone and nodal metastasis. The main objective of this review is to update the role of mpM RI prior to radical EBRT or SRT. We also consider future directions for the use and development of MRI in the field of radiation oncology.

The current role of prostate multiparametric magnetic resonance imaging

Prostate multi-parametric magnetic resonance imaging(mpMRI)has shown excellent sensitivity for Gleason
7 cancers,especially when their volume is
0.5 mL.As a result,performing an mpMRI before prostate biopsy could improve the detection of clinically significant prostate cancer(csPCa)by adding targeted biopsies to systematic biopsies.Currently,there is a consensus that targeted biopsies improve the detection of csPCa in the repeat biopsy setting and at confirmatory biopsy in patients considering active surveillance.Several prospective multicentric controlled trials recently showed that targeted biopsy also improved csPCa detection in biopsy-naǐve patients.The role of mpMRI and targeted biopsy during the follow-up of active surveillance remains unclear.Whether systematic biopsy could be omitted in case of negative mpMRI is also a matter of controversy.mpMRI did show excellent negative predictive values(NPV)in the literature,however,since NPV depends on the prevalence of the disease,negative mpMRI findings should be interpreted in the light of a priori risk for csPCa of the patient.Nomograms combining mpMRI findings and classical risk predictors(age,prostatespecific antigen density,digital rectal examination,etc.)will probably be developed in the future to decide whether a prostate biopsy should be obtained.mpMRI has a good specificity for detecting T3 stage cancers,but its sensitivity is low.It should therefore not be used routinely for staging purposes in low-risk patients.Nomograms combining mpMRI findings and other clinical and biochemical data will also probably be used in the future to better assess the risk of T3 stage disease.

Incremental value of magnetic resonance imaging in the advanced management of prostate cancer

Prostate cancer is a major public health burden throughout the world.The high incidence of prostate cancer,combined with earlier detection and downstaging at the time of diagnosis,and the slow natural progression and biological heterogeneity of the disease,has made its management a complex and controversial issue.There is growing demand for patient-specific therapies that can minimize treatment morbidity while maximizing treatment benefits.There are a number of clinical parameters and clinical nomograms to help with the choice of treatment.Magnetic resonance imaging(MRI)is a technique which makes safer,more individualized therapies possible due to high spatial resolution,superior contrast resolution,multiplanar capability,and a large field of view.Other MRI techniques such as MR spectroscopic imaging,dynamic contrast-enhanced MRI or perfusion MRI,and diffusion-weighted imaging complement MRI by reflecting tissue biochemistry,Brownian motion of water molecules,and capillary wall permeability,respectively.This editorial review highlights the incremental value of MRI in the advanced management of prostate cancer to non-invasively improve cancer staging,biologic potential,treatment planning,therapy response,local recurrence,and to guide target biopsy for clinical suspected cancer with previous negative biopsy.Finally,some future prospects for MRI in prostate cancer management are given.

The optimal timing of post-prostate biopsy magnetic resonance imaging to guide nerve-sparing surgery

The goal of our study was to evaluate the impact of the interval between prostate biopsy and magnetic resonance imaging （MRI） on the accuracy of simple tumor localization, which is essential information that enables nerve-sparing surgery. We also sought to determine the optimal timing of a post-biopsy MRI, A total of 184 patients who had undergone MRI before radical prostatectomy at an institution without a predetermined schedule for MRI after a prostate biopsy were enrolled. The mean interval from the biopsy to the MRI was 30.8 ± 18.6days. The accuracy of the MRI for simplified tumor location （right, left, bilateral and none） was 44.6%. In the group with discordant pathologic and MRI findings, the most common reason recorded was ＇MRI predicted a unilateral lesion, but pathology revealed bilateral lesions＇ （58.3%）, followed by ＇MRI predicted no lesion, but pathology revealed the presence of a lesion＇ （32.0%）. Multivariable analysis showed that the discordant group had a shorter interval （25.0 ± 14.3 vs 38.1 ± 20.6days, P 〈 0.01） preceding the MRI and a higher rate of hemorrhage as observed by MRI （80.4% vs 54.8%, P 〈 0.01） in comparison with the accordant group. In receiver operating characteristics analysis, the area under the curve of the MRI interval in accurate prediction of the tumor location was 0.707 （P 〈 0.001）. At the MRI interval＇s cutoff of 28.5days, the sensitivity was 73.2% and the specificity was 63.7%. When the MRI was performed within 28days, the accumulated accuracy was only 26.1% （23/88）; however, when it was performed after 28days, the reversely accumulated accuracy was 61.5% （59/96）. These data support a waiting period of at least 4weeks after a biopsy before performing an MRI for the purposes of surgical refinement.

Prostate magnetic resonance imaging at 3 Tesla:Is administration of hyoscine-N-butyl-bromide mandatory?

AIM: To evaluate the value of administration of hyoscine-N-butyl-bromide (HBB) for image quality magnetic resonance imaging (MRI) of the prostate. METHODS: Seventy patients were retrospectively included in the study. Thirty-five patients were examined with administration of 40 milligrams of HBB (Buscopan ; Boehringer, Ingelheim, Germany); 35 patients were examined without HBB. A multiparametric MRI protocol was performed on a 3.0 Tesla scanner without using an endorectal coil. The following criteria were evaluated independently by two experienced radiologists on a five-point Likert scale: anatomical details (delineation between peripheral and transitional zone of the prostate, visualisation of the capsule, depiction of the neurovascular bundles); visualisation of lymph nodes; motion related artefacts; and overall image quality.RESULTS: Comparison of anatomical details between the two cohorts showed no statistically significant difference (3.9 ± 0.7 vs 4.0 ± 0.9, P = 0.54, and 3.8 ± 0.7 vs 4.2 ± 0.6, P = 0.07) for both readers. There was no significant advantage regarding depiction of local and iliac lymph nodes (3.9 ± 0.6 vs 4.2 ± 0.6, P = 0.07, and 3.8 ± 0.9 vs 4.1 ± 0.8, P = 0.19). Motion arte- facts were rated as 'none' to 'few' in both groups and showed no statistical difference (2.3 ± 1.0 vs 1.9 ± 0.9, P = 0.19, and 2.3 ± 1.1 vs 1.9 ± 0.7, P = 0.22). Overall image quality was rated 'good' in average for both cohorts without significant difference (4.0 ± 0.6 vs 4.0 ± 0.9, P = 0.78, and 3.8 ± 0.8 vs 4.2 ± 0.6, P = 0.09). CONCLUSION: The results demonstrated no significant effect of HBB administration on image quality. The study suggests that use of HBB is not mandatory for MRI of the prostate at 3.0 Tesla.

Magnetic resonance imaging for prostate cancer clinical application

As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. In clinical practice, magnetic resonance imaging （MRI） is one of the imaging tools for the evaluation of prostate cancer, the fusion of MRI or dynamic contrast-enhanced MRI （DCE-MRI） with magnetic resonance spectroscopic imaging （MRSI） is improving the evaluation of cancer locafon, size, and extent, while providing an indication of tumor aggressiveness. This review summarizes the role of MRI in the application of prostate cancer and describes molecular MRI techniques （including MRSI and DCE-MRI） for aiding prostate cancer management.

Cognitive magnetic resonance imaging-ultrasound fusion transperineal targeted biopsy combined with randomized biopsy in detection of prostate cancer

BACKGROUND Prostate cancer(PCa)is one of the most common cancers among men.Various strategies for targeted biopsy based on multiparametric magnetic resonance imaging(mp-MRI)have emerged,which may improve the accuracy of detecting clinically significant PCa in recent years.AIM To investigate the diagnostic efficiency of a template for cognitive MRIultrasound fusion transperineal targeted plus randomized biopsy in detecting PCa.METHODS Data from patients with an increasing prostate-specific antigen(PSA)level but less than 20 ng/mL and at least one lesion suspicious for PCa on MRI from December 2015 to June 2018 were retrospectively analyzed.All patients underwent cognitive fusion transperineal template-guided targeted biopsy followed by randomized biopsy outside the targeted area.A total of 127 patients with complete data were included in the final analysis.A multivariable logistic regression analysis was conducted,and a two-sided P<0.05 was considered statistically significant.RESULTS PCa was detected in 66 of 127 patients,and 56 cases presented clinically significant PCa.Cognitive fusion targeted biopsy alone detected 59/127 cases of PCa,specifically 52/59 cases with clinically significant PCa and 7/59 cases with clinically insignificant PCa.A randomized biopsy detected seven cases of PCa negative on targeted biopsy,and four cases had clinically significant PCa.PSA density(OR:1.008,95%CI:1.003-1.012,P=0.001;OR:1.006,95%CI:1.002-1.010,P=0.004)and Prostate Imaging-Reporting and Data System(PI-RADS)scores(both P<0.001)were independently associated with the results of cognitive fusion targeted biopsy combined with randomized biopsy and targeted biopsy alone.CONCLUSION This single-centered study proposed a feasible template for cognitive MRIultrasound fusion transperineal targeted plus randomized biopsy.Patients with higher PSAD and PI-RADS scores were more likely to be diagnosed with PCa.

Role of serial multiparametric magnetic resonance imaging in prostate cancer active surveillance

AIM:To examine whether addition of 3T multiparametric magnetic resonance imaging(mp MRI)to an active surveillance protocol could detect aggressive or progressive prostate cancer.METHODS:Twenty-three patients with low risk disease were enrolled on this active surveillance study,all of which had Gleason score 6 or less disease.All patients had clinical assessments,including digital rectal examination and prostate specific antigen(PSA)testing,every 6 mo with annual 3T mp MRI scans with gadolinium contrast and minimum sextant prostate biopsies.The MRI images were anonymized of patient identifiers and clinical information and each scan underwentradiological review without the other results known.Descriptive statistics for demographics and follow-up as well as the sensitivity and specificity of mp MRI to identify prostate cancer and progressive disease were calculated.RESULTS:During follow-up(median 24.8 mo)11 of 23 patients with low-risk prostate cancer had disease progression and were taken off study to receive definitive treatment.Disease progression was identified through upstaging of Gleason score on subsequent biopsies for all 11 patients with only 2 patients also having a PSA doubling time of less than 2 years.All 23 patients had biopsy confirmed prostate cancer but only 10 had a positive index of suspicion on mp MRI scans at baseline(43.5% sensitivity).Aggressive disease prediction from baseline mpM RI scans had satisfactory specificity(81.8%)but low sensitivity(58.3%).Twentytwo patients had serial mp MRI scans and evidence of disease progression was seen for 3 patients all of whom had upstaging of Gleason score on biopsy(30% specificity and 100% sensitivity).CONCLUSION:Addition of mp MRI imaging in active surveillance decision making may help in identifying aggressive disease amongst men with indolent prostate cancer earlier than traditional methods.

Cavernosal nerve functionality evaluation after magnetic resonance imaging-guided transurethral ultrasound treatment of the prostate

AIM: To evaluate the feasibility of using therapeutic ultrasound as an alternative treatment option for organconfined prostate cancer. METHODS: In this study, a trans-urethral therapeutic ultrasound applicator in combination with 3T magnetic resonance imaging(MRI) guidance was used for realtime multi-planar MRI-based temperature monitoring and temperature feedback control of prostatic tissue thermal ablation in vivo. We evaluated the feasibility and safety of MRI-guided trans-urethral ultrasound to effectively and accurately ablate prostate tissue while minimizing the damage to surrounding tissues in eight canine prostates. MRI was used to plan sonications, monitor temperature changes during therapy, and to evaluate treatment outcome. Real-time temperature and thermal dose maps were calculated using the proton resonance frequency shift technique and were displayed as two-dimensional color-coded overlays on top of the anatomical images. After ultrasound treatment, an evaluation of the integrity of cavernosal nerves was performed during prostatectomy with a nerve stimulator that measured tumescence response quantitatively and indicated intact cavernous nerve functionality. Planned sonication volumes were visually correlated to MRI ablation volumes and corresponding histo-pathological sections after prostatectomy. RESULTS: A total of 16 sonications were performed in 8 canines. MR images acquired before ultrasound treatment were used to localize the prostate and to prescribe sonication targets in all canines. Temperature elevations corresponded within 1 degree of the targeted sonication angle, as well as with the width and length of the active transducer elements. The ultrasound treatment procedures were automatically interrupted when the temperature in the target zone reached 56 ℃. In all canines erectile responses were evaluated with a cavernous nerve stimulator post-treatment and showed a tumescence response after stimulation with an electric current. These results indicated intact cavernous nerve functionality. In all specimens, regions of thermal ablation were limited to areas within the prostate capsule and no damage was observed in periprostatic tissues. Additionally, a visual analysis of the ablation zones on contrast-enhanced MR images acquired post ultrasound treatment correlated excellent with the ablation zones on thermal dose maps. All of the ablation zones received a consensus score of 3(excellent) for the location and size of the correlation between the histologic ablation zone and MRI based ablation zone. During the prostatectomy and histologic examination, no damage was noted in the bladder or rectum.CONCLUSION: Trans-urethral ultrasound treatment of the prostate with MRI guidance has potential to safely, reliably, and accurately ablate prostatic regions, while minimizing the morbidities associated with conventional whole-gland resection or therapy.

DIFFERENTIATION BETWEEN BENIGN PROSTATIC HYPERPLASIA AND PROSTATE CANCER IN THE TRANSITIONAL ZONE EVALUATED BY ~1H MAGNETIC RESONANCE SPECTROSCOPIC IMAGING

Objective To quantitatively evaluate the metabolic changes of benign prostatic hyperplasia(BPH) and prostate cancer in the transitional zone using magnetic resonance spectroscopic imaging(MRSI),and to analyze the characteristics and differences of the spectra in this zonal area.Methods Eighteen patients with prostate cancer in the transitional zone underwent magnetic resonance imaging(MRI)/MRSI examinations.The(Choline+Creatine)/Citrate(CC/Ci) ratio and the Choline/Creatine(Cho/Cr) ratio were evaluated in each voxel with cancer or BPH confirmed by pathological results.Discriminant analysis was used to determine the power of the two ratios in differentiation between cancer and BPH.Results The CC/Ci ratio and Cho/Cr ratio for cancer voxels were significantly higher than those in the voxels with BPH in the transitional zone(CC/Ci:2.36±1.31 vs.0.85±0.29,P<0.01;Cho/Cr:4.14±1.79 vs.1.26±0.45,P<0.01).As for the discriminant function with the CC/Ci ratio and the Cho/Cr ratio,the specificity,sensitivity,and accuracy were 98.6%,85.7%,92.9% respectively for the differentiation between cancer and BPH.Conclusions The prostate cancer is characterized by higher CC/Ci ratio and Cho/Cr ratio compared to BPH in the transitional zone.Both CC/Ci ratio and Cho/Cr ratio have high specificity,sensitivity,and accuracy in their discriminative power between cancer and BPH in this zonal area.

Application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis

Objective The aim of the study was to investigate the application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis.Methods In the outpatient department of our hospital(Sichuan Cancer Hospital,Chengdu,China),60 patients diagnosed with prostate disease were selected randomly and included in a prostate cancer group,60 patients with benign prostatic hyperplasia were included in a proliferation group,and 60 healthy subjects were included in a control group,from January 2013 to January 2017.Using Siemens Avanto 1.5 T high-field superconducting MRI for DCE-MRI and MRS scans,after the MRS scan was completed,we used the workstation spectroscopy tab spectral analysis,and eventually obtained the crest lines of the prostate metabolites choline(Cho),creatine(Cr),citrate(Cit),and the values of Cho/Cit,and(Cho+Cr)/Cit.Results Participants who had undergone 21-s,1-min,and 2-min dynamic contrast-enhanced MR revealed significant variations among the three groups.The spectral analysis of the three groups revealed a significant variation as well.DCE-MRI and MRS combined had a sensitivity of 89.67%,specificity of 95.78%,and accuracy of 94.34%.Conclusion DCE-MRI combined with MRS is of great value in the diagnosis of prostate cancer.

Role of preoperative magnetic resonance imaging on the surgical outcomes of radical prostatectomy:Does preoperative tumor recognition reduce the positive surgical margin in a specific location?Experience from a Thailand prostate cancer specialized center

Objective Multiparametric magnetic resonance imaging(MRI)has become the standard of care for the diagnosis of prostate cancer patients.This study aimed to evaluate the influence of preoperative MRI on the positive surgical margin(PSM)rates.Methods We retrospectively reviewed 1070 prostate cancer patients treated with radical prostatectomy(RP)at Siriraj Hospital between January 2013 and September 2019.PSM rates were compared between those with and without preoperative MRI.PSM locations were analyzed.Results In total,322(30.1%)patients underwent MRI before RP.PSM most frequently occurred at the apex(33.2%),followed by posterior(13.5%),bladder neck(12.7%),anterior(10.7%),posterolateral(9.9%),and lateral(2.3%)positions.In preoperative MRI,PSM was significantly lowered at the posterior surface(9.0%vs.15.4%,p=0.01)and in the subgroup of urologists with less than 100 RP experiences(32%vs.51%,odds ratio=0.51,p<0.05).Blood loss was also significantly decreased when a preoperative image was obtained(200 mL vs.250 mL,p=0.02).Multivariate analysis revealed that only preoperative MRI status was associated with overall PSM and PSM at the prostatic apex.Neither the surgical approach,the neurovascular bundle sparing technique,nor the perioperative blood loss was associated with PSM.Conclusion MRI is associated with less overall PSM,PSM at apex,and blood loss during RP.Additionally,preoperative MRI has shown promise in lowering the PSM rate among urologists who are in the early stages of performing RP.