Feasibility of stereotactic optical navigation for needle positioning in percutaneous nephrolithotomy.

BACKGROUND: This study assessed the feasibility of acquiring single-attempt access to the pelvicalyceal system during percutaneous nephrolithotomy (PCNL) using stereotactic optical navigation combined with cone-beam CT (CBCT) imaging. METHODS: Patients with a PCNL indication were prospectively included in this IRB approved study. After sterile preparation, fiducial markers were attached to patients' skin. An initial intraprocedural CBCT scan was acquired, on which the urologist planned the needle trajectory using the navigation software. After verifying that no critical structures were crossed, the needle guide was aligned with the plan. A needle was manually inserted through the needle guide to the indicated depth and a second CBCT scan was performed for needle position confirmation. Both, scanning and needle insertion, were performed under apnea. The study evaluated technical success, accuracy, procedure time, complication rate, and radiation dose. RESULTS: Between June 2022 and April 2023, seven patients were included. In all patients, the navigation system allowed safe puncture. However, the technical success rate was only 29%. In 42% of the cases, pelvicalyceal access was achieved by a small manual adjustment. In the remaining 29%, the needle was retracted and positioned per clinical standard. The average deviation between the needle and target was 5.9 ± 2.3 mm. The average total procedure time was 211 ± 44 min. The average radiation exposure was 6.4 mSv, with CBCT scanning contributing to 82% of this exposure. CONCLUSIONS: The optical navigation system facilitated safe needle insertion but did not consistently ensure accurate one-attempt needle positioning for PCNL. Real-time visualization and trajectory correction may improve the technical success rate.

Ablative margins in percutaneous thermal ablation of hepatic tumors: a systematic review.

INTRODUCTION: This study aims to systematically review current evidence on ablative margins and correlation to local tumor progression (LTP) after thermal ablation of hepatocellular carcinoma (HCC) and colorectal liver metastases (CRLM). METHODS: A systematic search was performed in PubMed (MEDLINE) and Web of Science to identify all studies that reported on ablative margins (AM) and related LTP rates. Studies were assessed for risk of bias and synthesized separately per tumor type. Where possible, results were pooled to calculate risk differences (RD) as function of AM. RESULTS: In total, 2910 articles were identified of which 43 articles were eligible for final analysis. There was high variability in AM measurement methodology across studies in terms of measurement technique, imaging modalities, and timing. Most common margin stratification was < 5 mm and > 5 mm, for which data were available in 25/43 studies (58%). Of these, all studies favored AM > 5 mm to reduce the risk of LTP, with absolute RD of 16% points for HCC and 47% points for CRLM as compared to AM < 5 mm. CONCLUSIONS: Current evidence supports AM > 5 mm to reduce the risk of LTP after thermal ablation of HCC and CRLM. However, standardization of AM measurement and reporting is critical to allow future meta-analyses and improved identification of optimal threshold value for clinical use.

The accuracy of navigated versus freehand curettage in bone tumors: a cadaveric model study.

PURPOSE: Navigation has been suggested to guide complex benign bone tumor curettage procedures, but the contribution of navigation to the accuracy of curettage has never been quantified. We explored the accuracy of navigated curettage in a cadaveric observational pilot study, comparing navigated to freehand curettage, performed independently by an expert and a novice user. METHODS: The expert performed curettage on 20 cadaveric bones prepared with a paraffin wax mixture tumor, 10 freehand and 10 navigated. We re-used 12 bones for the novice experiments, 6 freehand and 6 navigated. Tumor and curettage cavity volumes were segmented on pre- and post-cone-beam CT scans. Accuracy was quantified using the Dice Similarity Coefficient (DSC), and with remaining tumor volume, bone curettage volume, maximal remaining width and procedure times compared between navigation and freehand groups for both users. RESULTS: There were little differences in curettage accuracy between a navigated (DSC 0.59[0.17]) and freehand (DSC 0.64[0.10]) approach for an expert user, but there were for a novice user with DSC 0.67(0.14) and 0.83(0.06), respectively. All navigated and freehand procedures had some amount of remaining tumor, generally located in a few isolated spots with means of 2.2(2.6) cm3 (mean 20% of the tumor volume) and 1.5(1.4) cm3 (18%), respectively, for the expert and more diffusely spaced with means of 5.1(2.8) cm3 (33%) and 3.0(2.2) cm3 (17%), respectively, for the novice. CONCLUSIONS: In an explorative study on 20 cadaveric bone tumor models, navigated curettage in its current setup was not more accurate than freehand curettage. The amount of remaining tumor, however, confirms that curettage could be further improved. The novice user was less accurate using navigation than freehand, which could be explained by the learning curve. Furthermore, the expert used a different surgical approach than the novice, focusing more on removing the entire tumor than sparing surrounding bone.

AI-assisted biparametric MRI surveillance of prostate cancer: feasibility study.

OBJECTIVES: To evaluate the feasibility of automatic longitudinal analysis of consecutive biparametric MRI (bpMRI) scans to detect clinically significant (cs) prostate cancer (PCa). METHODS: This retrospective study included a multi-center dataset of 1513 patients who underwent bpMRI (T2 + DWI) between 2014 and 2020, of whom 73 patients underwent at least two consecutive bpMRI scans and repeat biopsies. A deep learning PCa detection model was developed to produce a heatmap of all PIRADS ≥ 2 lesions across prior and current studies. The heatmaps for each patient's prior and current examination were used to extract differential volumetric and likelihood features reflecting explainable changes between examinations. A machine learning classifier was trained to predict from these features csPCa (ISUP > 1) at the current examination according to biopsy. A classifier trained on the current study only was developed for comparison. An extended classifier was developed to incorporate clinical parameters (PSA, PSA density, and age). The cross-validated diagnostic accuracies were compared using ROC analysis. The diagnostic performance of the best model was compared to the radiologist scores. RESULTS: The model including prior and current study (AUC 0.81, CI: 0.69, 0.91) resulted in a higher (p = 0.04) diagnostic accuracy than the current only model (AUC 0.73, CI: 0.61, 0.84). Adding clinical variables further improved diagnostic performance (AUC 0.86, CI: 0.77, 0.93). The diagnostic performance of the surveillance AI model was significantly better (p = 0.02) than of radiologists (AUC 0.69, CI: 0.54, 0.81). CONCLUSIONS: Our proposed AI-assisted surveillance of prostate MRI can pick up explainable, diagnostically relevant changes with promising diagnostic accuracy. KEY POINTS: • Sequential prostate MRI scans can be automatically evaluated using a hybrid deep learning and machine learning approach. • The diagnostic accuracy of our csPCa detection AI model improved by including clinical parameters.

Propensity score matching demonstrates similar results for radiofrequency ablation compared to surgical resection in colorectal liver metastases.

PURPOSE: Minimally invasive ablative treatments, such as radiofrequency ablation (RFA), are increasingly used in the curative treatment of patients with colorectal liver metastases (CRLM). Selection bias plays an important role in the evaluation of early and late results between RFA and surgery. The purpose of this study was to evaluate recurrences and oncological survival following these two treatment modalities using single pair propensity score matching. METHODS: Between 2000 and 2018, patients curatively treated for CRLM were included in a multicentre database. Patients were excluded when receiving two-staged treatment, synchronous treatment with primary tumor or combination of modalities. Propensity score matching was used to minimize influence of known covariates, i.e., age, ASA, FONG CRS, location and T-stage of the primary tumor. RESULTS: Before matching, the RFA group contained 39 patients and the surgery group 982 patients, after matching both groups contained 36 patients. After matching, mean age was 69 years (53-86) for RFA and 68 (50-86) for surgery, with a mean tumor size of respectively 2.5 cm (0.8-6.5) and 3.4 cm (1-7.5). Both groups showed similar complication rate according to Clavien-Dindo (17vs.33%; p = 0.18), recurrence rate (58vs.64%; p = 0.09) without significant differences in 5-year DFS and OS (RFA compared to surgery respectively 25vs.37%; p = 0.09 and 42vs.53%; p = 0.09). CONCLUSION: After propensity score matching, RFA showed lower complications and similar oncological survival compared to surgical resection. In patients who are suboptimal candidates for surgery, RFA seems to be a good and safe alternative.

Software-based planning of ultrasound and CT-guided percutaneous radiofrequency ablation in hepatic tumors.

OBJECTIVES: Radiofrequency ablation (RFA) can be associated with local recurrences in the treatment of liver tumors. Data obtained at our center for an earlier multinational multicenter trial regarding an in-house developed simulation software were re-evaluated in order to analyze whether the software was able to predict local recurrences. METHODS: Twenty-seven RFA ablations for either primary or secondary hepatic tumors were included. Colorectal liver metastases were shown in 14 patients and hepatocellular carcinoma in 13 patients. Overlap of the simulated volume and the tumor volume was automatically generated and defined as positive predictive value (PPV) and additionally visually assessed. Local recurrence during follow-up was defined as gold standard. Sensitivity and specificity were calculated using the visual assessment and gold standard. RESULTS: Mean tumor size was 18 mm (95% CI 15-21 mm). Local recurrence occurred in 5 patients. The PPV of the simulation showed a mean of 0.89 (0.84-0.93 95% CI). After visual assessment, 9 incomplete ablations were observed, of which 4 true positives and 5 false positives for the detection of an incomplete ablation. The sensitivity and specificity were, respectively, 80% and 77% with a correct prediction in 78% of cases. No significant correlation was found between size of the tumor and PPV (Pearson Correlation 0.10; p = 0.62) or between PPV and recurrence rates (Pearson Correlation 0.28; p = 0.16). CONCLUSIONS: The simulation software shows promise in estimating the completeness of liver RFA treatment and predicting local recurrence rates, but could not be performed real-time. Future improvements in the field of registration could improve results and provide a possibility for real-time implementation.

Does perfusion computed tomography correlate to pathology in colorectal liver metastases?

INTRODUCTION: Targeted therapy against tumor angiogenesis is widely used in clinical practice for patients with colorectal liver metastases (CRLM). Possible predictive biomarkers for tumor angiogenesis, such as, microvessel density (MVD), hypoxia and cell proliferation, can be determined using immunohistochemical staining. However, patients ineligible for surgical treatment need to undergo invasive diagnostic interventions in order to determine these biomarkers. CT perfusion (CTP) is an emerging functional imaging technique, which can non-invasively determine vascular properties of solid tumors. The purpose of this study was to evaluate CTP with histological biomarkers in CRLM. MATERIAL AND METHODS: Patients with CRLM underwent CTP one day before liver surgery. CTP analysis was performed on the entire volume of the largest metastases in each patient. Dual-input maximum slope analysis was used and data concerning arterial flow (AF), portal flow (PF) and perfusion index (PI) were recorded. Immunohistochemical staining with CD34, M75/CA-IX and MIB-1 was performed on the rim in the midsection of the tumor to determine respectively MVD, hypoxia and cell proliferation. RESULTS: Twenty CRLM in 20 patients were studied. Mean size of the largest CRLM was 37 mm (95% CI 21-54 mm). Mean AF and PF were respectively 64 ml/min/100ml (95% CI 48-79) and 30 ml/min/100ml (95% CI 22-38). Mean PI was 68% (95% CI 62-73). No significant correlation was found between tumor growth patterns and CTP (p = 0.95). MVD did not significantly correlate to AF (r = 0.05; p = 0.84), PF (r = 0.17; p = 0.47) and PI (r = -0.12; p = 0.63). Cell proliferation also did not significantly correlate to AF (r = 0.07; p = 0.78), PF (r = -0.01; p = 0.95) and PI (r = 0.15; p = 0.52). Hypoxia did not significantly correlate to AF (r = -0.05; p = 0.83), however, significantly to PF (r = 0.51; p = 0.02) and a trend to negative correlation with PF (r = -0.43; p = 0.06). However, after controlling the false discovery rate, no significant correlation between CTP and used immunohistochemical biomarkers was found. CONCLUSION: In conclusion, this feasibility study found a trend to negative correlation between PI and hypoxia, CTP might therefore possibly evaluate this prognostic marker in CRLM non-invasively. However, CTP is not an appropriate technique for the assessment of microvessels or cell proliferation in CRLM.

Urinary incontinence and erectile dysfunction in patients with localized or locally advanced prostate cancer: A nationwide observational study.

BACKGROUND: Although urinary adverse events after treatment of prostate cancer (CaP) are common, population-based studies on functional outcomes are scarce. The aim of this study is to evaluate the occurrence of urinary incontinence (UI) and erectile dysfunction (ED) in daily clinical practice using a nationwide Dutch cohort of patients with localized or locally advanced CaP. BASIC PROCEDURES: Patients were invited to complete the EPIC-26 questionnaire before treatment (baseline) and at 12 and 24 months after diagnosis. We calculated the mean EPIC-26 domain scores, stratified by treatment modality (i.e., radical prostatectomy, external radiotherapy, and no active treatment), and the proportions of patients with UI (defined as ≥ 2 pads per day) and ED (defined as erections not firm enough for sexual intercourse). Logistic regression modeling was used to explore the factors related to UI and ED after surgery. MAIN FINDINGS: In total 1,759 patients participated in this study. Patients undergoing radical prostatectomy experienced clinically relevant worsening in the urinary incontinence domain. After excluding patients who reported UI at baseline, 15% of patients with prostatectomy reported UI 24 months after diagnosis. Only comorbidity was associated with UI in surgically treated patients. Regardless of treatment, patients reported a clinically significant reduced sexual functioning over time. Before treatment, 54% of patients reported ED. Among the 46% remaining patients, 87% of patients treated with radical prostatectomy reported ED 24 months after diagnosis, 41% after radiotherapy, and 46% in patients without active treatment. Bilateral nerve-sparing surgery was the only factor associated with ED after 24 months. PRINCIPAL CONCLUSIONS: UI and ED frequently occur in patients with localized and locally advanced CaP, in particular after radical prostatectomy. The higher occurrence rate of UI and ED, compared with clinical trial participants, supports the importance of real-world data, which can be used for local treatment recommendations and patient information, but also to evaluate effects of future initiatives, such as treatment centralization and research aimed at improving functional outcomes.

Performance of single-use syringe versus multi-use MR contrast injectors: a prospective comparative study.

The goal of this study was to compare performance parameters of a single-use syringe and a multi-use MR contrast injector. We compared preparation time, cost for disposables and volumes of contrast material used for a single-use (SI) and a multi-use (MI) MR contrast injector in a prospective cross-over trial. During the first study period all consecutive patients eligible for dynamic MR on two systems were included during a period of 20 working days. After 10 days, the injector was switched. Radiographer satisfaction was evaluated using a questionnaire. Contrast usage and waste on system MI was optimised by extra instructions for our radiographers and measured during the second study period of 10 consecutive working days. A total of 202 and 163 patients for systems SI and MI were included, respectively. Average preparation time was 4:55 min for SI and 2:24 min for MI (p < 0.05). Contrast waste for SI was 13% using 7.5 ml syringes. Contrast waste for MI was 5% for 7.5 ml containers. Costs for disposables were lower for MI if more than 5 patients per day were injected. Radiographer satisfaction was higher for MI (4.7 versus 2.8 on a 5-point scale; p < 0.05). The multi-use MR contrast injector led to higher radiographer satisfaction, shorter preparation time, and lower cost if more than 5 patients were injected per day. In addition, cheaper contrast containers of 15 or 30 ml could be used for the first patients if more than 2 or more than 4 injections are performed per day, potentially leading to lower contrast waste.

68Ga-PSMA-PET/CT and Diffusion MRI Targeting for Cone-Beam CT-Guided Bone Biopsies of Castration-Resistant Prostate Cancer Patients.

INTRODUCTION: Precision medicine expands the treatment options for metastatic castration-resistant prostate cancer (mCRPC) by targeting druggable genetic aberrations. Aberrations can be identified following molecular analysis of metastatic tissue. Bone metastases, commonly present in mCRPC, hinder precision medicine due to a high proportion of biopsies with insufficient tumor cells for next-generation DNA sequencing. We aimed to investigate the feasibility of incorporating advanced target planning and needle guidance in bone biopsies and whether this procedure increases biopsy tumor yield and success rate of molecular analysis as compared to the current standards, utilizing only CT guidance. MATERIALS AND METHODS: In a pilot study, ten mCRPC patients received 68Ga-prostate-specific membrane antigen (PSMA)-PET/CT and diffusion-weighted MRI as biopsy planning images. These datasets were fused for targeting metastatic lesions with high tumor densities. Biopsies were performed under cone-beam CT (CBCT) guidance. Feasibility of target planning and needle guidance was assessed, and success of molecular analysis and tumor yield were reported. RESULTS: Fusion target planning and CBCT needle guidance were feasible. Nine out of ten biopsies contained prostate cancer cells, with a median of 39% and 40% tumor cells by two different sequencing techniques. Molecular analysis was successful in eight of ten patients (80%). This exceeds previous reports on CT-guided biopsies that ranged from 33 to 44%. In two patients, important druggable aberrations were found. DISCUSSION: A biopsy procedure using advanced target planning and needle guidance is feasible and can increase the success rate of molecular analysis in bone metastases, thereby having the potential of improving treatment outcome for patients with mCRPC. LEVEL OF EVIDENCE: Level 4, case series.

EAU-ESMO consensus statements on the management of advanced and variant bladder cancer-an international collaborative multi-stakeholder effort: under the auspices of the EAU and ESMO Guidelines Committees†.

BACKGROUND: Although guidelines exist for advanced and variant bladder cancer management, evidence is limited/conflicting in some areas and the optimal approach remains controversial. OBJECTIVE: To bring together a large multidisciplinary group of experts to develop consensus statements on controversial topics in bladder cancer management. DESIGN: A steering committee compiled proposed statements regarding advanced and variant bladder cancer management which were assessed by 113 experts in a Delphi survey. Statements not reaching consensus were reviewed; those prioritised were revised by a panel of 45 experts before voting during a consensus conference. SETTING: Online Delphi survey and consensus conference. PARTICIPANTS: The European Association of Urology (EAU), the European Society for Medical Oncology (ESMO), experts in bladder cancer management. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Statements were ranked by experts according to their level of agreement: 1-3 (disagree), 4-6 (equivocal), 7-9 (agree). A priori (level 1) consensus was defined as ≥70% agreement and ≤15% disagreement, or vice versa. In the Delphi survey, a second analysis was restricted to stakeholder group(s) considered to have adequate expertise relating to each statement (to achieve level 2 consensus). RESULTS AND LIMITATIONS: Overall, 116 statements were included in the Delphi survey. Of these, 33 (28%) statements achieved level 1 consensus and 49 (42%) statements achieved level 1 or 2 consensus. At the consensus conference, 22 of 27 (81%) statements achieved consensus. These consensus statements provide further guidance across a broad range of topics, including the management of variant histologies, the role/limitations of prognostic biomarkers in clinical decision making, bladder preservation strategies, modern radiotherapy techniques, the management of oligometastatic disease and the evolving role of checkpoint inhibitor therapy in metastatic disease. CONCLUSIONS: These consensus statements provide further guidance on controversial topics in advanced and variant bladder cancer management until a time where further evidence is available to guide our approach.

Results after simultaneous surgery and RFA liver ablation for patients with colorectal carcinoma and synchronous liver metastases.

BACKGROUND: Approximately 20% of patients with colorectal cancer present with synchronous liver metastases (sCRLM). These patients can be treated with a "one-step procedure" or staged resection, with or without radiofrequency ablation (RFA). Colorectal surgery in combination with intraoperative RFA leads to concerns regarding postoperative complications and survival. The purpose was to evaluate the one-step procedure with or without RFA in patients with sCRLM. MATERIALS AND METHODS: Between January 2000 and September 2018, patients with sCRLM were selected in two tertiary referral centers and retrospectively analyzed. Postoperative morbidity and survival were analyzed. RESULTS: From a total of 410 patients presenting with sCRLM, 329 patients underwent a staged resection and 81 a one-step procedure. The 3-year overall survival (OS) was respectively 66% and 69% for one-step procedure and staged resection (P = 0.24). A total of 18 patients underwent RFA during the one step procedure. No significant differences were shown in postoperative complications whether intraoperative RFA was used in patients with sCRLM. In the one-step procedure, the 3-year OS was respectively 43% and 72% wheter patients did or did not receive RFA (P = 0.19). CONCLUSION: OS for patients with sCRLM was similar for both one-step procedure and staged resection. Intraoperative RFA for sCRLM is technically safe.

Focal laser ablation as clinical treatment of prostate cancer: report from a Delphi consensus project.

PURPOSE: To define the role of focal laser ablation (FLA) as clinical treatment of prostate cancer (PCa) using the Delphi consensus method. METHODS: A panel of international experts in the field of focal therapy (FT) in PCa conducted a collaborative consensus project using the Delphi method. Experts were invited to online questionnaires focusing on patient selection and treatment of PCa with FLA during four subsequent rounds. After each round, outcomes were displayed, and questionnaires were modified based on the comments provided by panelists. Results were finalized and discussed during face-to-face meetings. RESULTS: Thirty-seven experts agreed to participate, and consensus was achieved on 39/43 topics. Clinically significant PCa (csPCa) was defined as any volume Grade Group 2 [Gleason score (GS) 3+4]. Focal therapy was specified as treatment of all csPCa and can be considered primary treatment as an alternative to radical treatment in carefully selected patients. In patients with intermediate-risk PCa (GS 3+4) as well as patients with MRI-visible and biopsy-confirmed local recurrence, FLA is optimal for targeted ablation of a specific magnetic resonance imaging (MRI)-visible focus. However, FLA should not be applied to candidates for active surveillance and close follow-up is required. Suitability for FLA is based on tumor volume, location to vital structures, GS, MRI-visibility, and biopsy confirmation. CONCLUSION: Focal laser ablation is a promising technique for treatment of clinically localized PCa and should ideally be performed within approved clinical trials. So far, only few studies have reported on FLA and further validation with longer follow-up is mandatory before widespread clinical implementation is justified.

MR imaging-guided prostate interventional imaging: Ready for a clinical use?

Prostate interventional magnetic resonance imaging (MRI) is now routinely performed in many centers. Its more widespread acceptance is limited by the cost of the use of MRI largely related to the long duration time of the procedures. However, the benefit of a robotic assistance has generated a new interest, because it substantially shortens the procedure time, while improving the accuracy. MRI-guided biopsy is considered as an appealing alternative to transrectal ultrasound (TRUS)-guided fusion biopsy, given the limitations of TRUS-MRI image registration systems. MRI-guided focal treatment also benefits from robotic assistance and from the unique property of MRI, which allows the measurement of the temperature in real-time during tumor ablation. The transrectal and transperineal approaches can be used and the respective indications of each pathway will depend on several factors, including the location of the tumor and the examination time, which will condition the occupation time of the MR room, a major factor influencing the overall cost of MRI-guided procedures. This review addresses the current practice of prostate MRI-guided interventional procedures and potential future applications.

Medical students' perspective on training in anatomy.

Gaining sufficient knowledge of anatomy is an important part of medical education. Factors that influence how well students learn anatomical structures include available sources, learning time and study assistance. This study explores the attitude of medical students with regard to studying anatomy and evaluates possibilities for improvement of training in anatomy. Twenty medical students participated in a focus group meeting. Based on this focus group, an online survey consisting of 27 questions was developed and distributed amongst medical students of Maastricht University, the Netherlands. A total of 495 medical students (both Bachelor and Master level) participated in this survey. Master students found studying anatomy less attractive than Bachelor students (36.8% of the Master students vs. 47.9% of the Bachelor students (p=.024)). Although most students responded that they thought it is important to study anatomy, 48% of all students studied anatomy less than 10h per study block of 8 weeks. Only 47.9% of the students rated their knowledge of anatomy as adequate. Students suggested that three-dimensional techniques would help improve their knowledge of anatomy. Therefore investing in three-dimensional tools could prove beneficial in the future.

Utilization of multiparametric prostate magnetic resonance imaging in clinical practice and focal therapy: report from a Delphi consensus project.

PURPOSE: To codify the use of multiparametric magnetic resonance imaging (mpMRI) for the interrogation of prostate neoplasia (PCa) in clinical practice and focal therapy (FT). METHODS: An international collaborative consensus project was undertaken using the Delphi method among experts in the field of PCa. An online questionnaire was presented in three consecutive rounds and modified each round based on the comments provided by the experts. Subsequently, a face-to-face meeting was held to discuss and finalize the consensus results. RESULTS: mpMRI should be performed in patients with prior negative biopsies if clinical suspicion remains, but not instead of the PSA test, nor as a stand-alone diagnostic tool or mpMRI-targeted biopsies only. It is not recommended to use a 1.5 Tesla MRI scanner without an endorectal or pelvic phased-array coil. mpMRI should be performed following standard biopsy-based PCa diagnosis in both the planning and follow-up of FT. If a lesion is seen, MRI-TRUS fusion biopsies should be performed for FT planning. Systematic biopsies are still required for FT planning in biopsy-naïve patients and for patients with residual PCa after FT. Standard repeat biopsies should be taken during the follow-up of FT. The final decision to perform FT should be based on histopathology. However, these consensus statements may differ for expert centers versus non-expert centers. CONCLUSIONS: The mpMRI is an important tool for characterizing and targeting PCa in clinical practice and FT. Standardization of acquisition and reading should be the main priority to guarantee consistent mpMRI quality throughout the urological community.

Comparison of dynamic magnetic resonance defaecography with rectal contrast and conventional defaecography for posterior pelvic floor compartment prolapse.

AIM: This study compared the diagnostic capabilities of dynamic magnetic resonance defaecography (D-MRI) with conventional defaecography (CD, reference standard) in patients with symptoms of prolapse of the posterior compartment of the pelvic floor. METHOD: Forty-five consecutive patients underwent CD and D-MRI. Outcome measures were the presence or absence of rectocele, enterocele, intussusception, rectal prolapse and the descent of the anorectal junction on straining, measured in millimetres. Cohen's Kappa, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and the positive and negative likelihood ratio of D-MRI were compared with CD. Cohen's Kappa and Pearson's correlation coefficient were calculated and regression analysis was performed to determine inter-observer agreement. RESULTS: Forty-one patients were available for analysis. D-MRI underreported rectocele formation with a difference in prevalence (CD 77.8% vs D-MRI 55.6%), mean protrusion (26.4 vs 22.7 mm, P = 0.039) and 11 false negative results, giving a low sensitivity of 0.62 and a NPV of 0.31. For the diagnosis of enterocele, D-MRI was inferior to CD, with five false negative results, giving a low sensitivity of 0.17 and high specificity (1.0) and PPV (1.0). Nine false positive intussusceptions were seen on D-MRI with only two missed. CONCLUSION: The accuracy of D-MRI for diagnosing rectocele and enterocele is less than that of CD. D-MRI, however, appears superior to CD in identifying intussusception. D-MRI and CD are complementary imaging techniques in the evaluation of patients with symptoms of prolapse of the posterior compartment.

Feasibility of a 2nd generation MR-compatible manipulator for transrectal prostate biopsy guidance.

OBJECTIVES: To assess the feasibility of a 2nd generation MR-compatible, remote-controlled manipulator (RCM) as an aid to perform MR-guided transrectal prostate biopsy in males with suspicion of prostate cancer (PCa). METHODS: This prospective phase I study was approved by the local ethical committee and written informed consent was obtained from each patient. Twenty patients with ≥1 cancer suspicious region (CSR) with a PI-RADS score of ≥3 detected on the diagnostic multi-parametric MRI and no prior prostate treatment underwent MR-guided biopsy with the aid of the RCM. Complications were classified according to the modified Clavien system for reporting surgical complications. For evaluation of the workflow, procedure- and manipulation times were recorded. RESULTS: All CSR's (n=20) were reachable with the MR-compatible RCM and the cancer detection rate was 70 %. The median procedure time was 36:44 minutes (range, 23 - 61 minutes) and the median manipulation time for needle guide movement was 5:48 minutes (range, 1:15 - 18:35 minutes). Two Clavien grade 1 complications were reported. CONCLUSIONS: It is feasible and safe to perform transrectal MR-guided prostate biopsy using a MR-compatible RCM as an aid. It is a fast and efficient way to biopsy suspicious prostate lesions with a minimum number of biopsies per patient. KEY POINTS: • It is feasible to perform transrectal prostate biopsy using a MR-compatible RCM. • Using a RCM for MR-guided biopsy is safe, fast, and efficient. • All cancer suspicious regions were reachable with the RCM.

Short term and long term results of patients with colorectal liver metastases undergoing surgery with or without radiofrequency ablation.

PURPOSE: The combination of resection and radiofrequency ablation (RFA) may provide an alternative treatment for patients with unresectable colorectal liver metastases (CRLM). Although the results in literature look promising, uncertainty exists with regard to complication risks and survival for this therapy. METHODS: From January 2000 to May 2013, patients were included in a prospective multicenter database when treated for CRLM. Exclusion criteria were: two-staged treatment, synchronous resection of liver metastases and primary tumor, loss to follow-up or extrahepatic metastases. Patients were divided in a resection-only group (ROG) and combination group (CG). Outcome variables were retrospectively analyzed. RESULTS: In CG, 98 patients were included versus 534 patients in ROG. There were no differences in general patient characteristics. Patients in CG had a higher Fong clinical risk score (CRS; P = 0.001), better ASA classification (P = 0.04) and received more neoadjuvant chemotherapy (P = 0.001). There was no difference in postoperative morbidity or 90-day mortality. The 5-year disease-free survival (DFS) for CG and ROG was 25% and 36.1% (P = 0.03), respectively. For the 5-year overall survival (OS) this was respectively 42% and 62.2% (P = 0.001). On multivariate analysis, Fong CRS was a significant predictor for DFS. For OS, Fong CRS, ASA class IV and the combination therapy were significant predictors. CONCLUSION: The combination of hepatic resection and intraoperative RFA is a safe procedure, without increase in postoperative morbidity or mortality. Combining RFA and resection in one session is a valid treatment option for patients who would otherwise be inoperable.