[Radiation-induced cataract-an occult risk for urologists]. / Strahleninduzierter Katarakt ­ ein okkultes Berufsrisiko für Urologen.

BACKGROUND: Radiation-induced cataracts represent a relevant risk to people occupationally exposed to radiation. The annual limit dose for the eye lens was reduced to 20 mSv per year by German legislation (radiation protect law StrlSchG 2017; 2013/59/Euratom) based on recommendation of International Commission on Radiation Protection (2011 ICRP) to avoid radiation-induced cataracts. OBJECTIVES: Is there a risk of exceeding the annual limit dose for the eye lens in routine urological practice without special radiation protection for the head? METHODS: As part of a prospective, monocentric dosimetry study, of 542 different urological, fluoroscopically guided interventions, the eye lens dose was determined using a forehead dosimeter (thermo-luminescence dosemeter TLD, Chipstrate) over a period of 5 months. RESULTS: An average head dose of 0.05 mSv per intervention (max. 0.29 mSv) was found with an average dose area product of 485.33 Gy/cm2. Significant influencing factors for a higher dose were a higher patient body mass index (BMI), a longer operation time, and a higher dose area product. The level of experience of the surgeon showed no significant influence. DISCUSSION: With 400 procedures per year or an average of 2 procedures per working day, the critical annual limit value for the eye lenses or for the risk of radiation-induced cataract would be exceeded without special protective measures. CONCLUSION: Consistently effective radiation protection of the eye lens is essential for daily work in uroradiological interventions. This may require further technical developments.

Prospective evaluation of CT-guided HDR brachytherapy as a local ablative treatment for renal masses: a single-arm pilot trial.

PURPOSE: In this pilot trial, we investigate the safety of CT-guided high-dose-rate brachytherapy (HDR-BT) as a local ablative treatment for renal masses not eligible for resection or nephrectomy. METHODS: We investigated renal function after irradiation by HDR-BT in 16 patients (11 male, 5 female, mean age 76 years) with 20 renal lesions (renal cell carcinoma n = 18; renal metastases n = 2). Two patients had previous contralateral nephrectomy and two had ipsilateral partial nephrectomy. Six lesions had a hilar localization with proximity to the renal pelvis and would have not been favorable for thermal ablation. Renal function loss was determined within 1 year after HDR-BT by renal scintigraphy and laboratory parameters. Further investigations included CT and MRI every 3 months to observe procedural safety and local tumor control. Renal function tests were analyzed by Wilcoxon's signed rank test with Bonferroni-Holm correction of p-values. Survival and local tumor control underwent a Kaplan-Meier estimation. RESULTS: Median follow-up was 22.5 months. One patient required permanent hemodialysis 32 months after repeated HDR-BT and contralateral radiofrequency ablation of multifocal renal cell carcinoma. No other patient developed a significant worsening in global renal function and no gastrointestinal or urogenital side effects were observed. Only one patient died of renal tumor progression. Local control rate was 95% including repeated HDR-BT of two recurrences. CONCLUSION: HDR-BT is a feasible and safe technique for the local ablation of renal masses. A phase II study is recruiting to evaluate the efficacy of this novel local ablative treatment in a larger study population.

[Small renal cell carcinoma-active surveillance and ablation]. / Kleines Nierenzellkarzinom ­ Aktive Überwachung und Ablation.

The incidence of renal cell carcinoma has been rising for years. At the same time there is an increasing prevalence of chronic renal failure with subsequent higher morbidity and shorter life expectancy in those affected. In the last decades the gold standard has thus shifted from radical to partial nephrectomy or tumor enucleation. A treatment alternative can be advantageous for selected patients with high morbidity and an increased risk of complications in anesthesia or surgery. Active surveillance represents a controlled delay in the initiation of treatment with a curative intention. Percutaneous radiofrequency ablation and laparoscopic cryoablation are currently the most commonly used treatment alternatives. Newer ablation procedures, such as high-intensity focused ultrasound, irreversible electroporation, microwave ablation, stereotactic ablative radiotherapy and high-dose brachytherapy have a high potential in some cases but are still considered experimental for the treatment.

Upper-Urinary-Tract Effects After Irreversible Electroporation (IRE) of Human Localised Renal-Cell Carcinoma (RCC) in the IRENE Pilot Phase 2a Ablate-and-Resect Study.

PURPOSE: Irreversible electroporation (IRE) is a new potential ablation modality for small renal masses. Animal experiments have shown preservation of the urine-collecting system (UCS). The purpose of this clinical study was to perform the first evaluation and comparison of IRE's effects on the renal UCS by using urinary cytology, magnetic-resonance imaging, and resection histology in men after IRE of pT1a renal-cell carcinoma (RCC). METHODS: Seven patients with biopsy-proven RCC pT1a cN0cM0 underwent IRE in a phase 2a pilot ablate-and-resect study (IRENE trial). A contrast-enhanced, diffusion-weighted MRI and urinary cytology was performed 1 day before and 2, 7, and 27 days after IRE. Twenty-eight days after IRE the tumour region was completely resected surgically. RESULTS: Technical feasibility was demonstrated in all patients. In all cases, MRI revealed complete coverage of the tumour area by the ablation zone with degenerative change. The urographic late venous MRI phase (urogram scans) demonstrated normal morphological appearances. Urine cytology showed a temporary vacuolisation of the cyto- and caryoplasmas after IRE. Whereas the urothelium showed signs of regeneration 28 days after IRE-ablation, the tumour and parenchyma below it showed necrosis and permanent tissue destruction. CONCLUSIONS: Renal percutaneous IRE appears to be a safe treatment for pT1a RCC. The preservation of the UCS with unaltered normal morphology as well as urothelial regeneration and a phenomenon (new in urinary cytology) of temporary degeneration with vacuolisation of detached transitional epithelium cells were demonstrated in this clinical pilot study.

[Focal therapy of prostate cancer]. / Fokale Therapie des Prostatakarzinoms.

The target of focal therapy (FT) in prostate cancer (PC) is partial treatment of the prostate aiming at preserving surrounding anatomical structures. The intention is to minimize typical side effects of radical treatment options combined with local tumor control. Numerous established and new technologies are used. Results of published studies showed a good safety profile, few side effects and good preservation of functional results. Oncologic long-term data are lacking so far. Photodynamic therapy (PDT) is the only technology that has been studied in a published prospective randomized trial. The FT is challenged by the multifocality of PC; therefore, the quality of prostate biopsy, histopathological assessment as well as imaging are of paramount importance. Multiparametric magnetic resonance imaging (MRI) has gained increasing importance. The FT is experimental and should only be offered within clinical trials.

[Prostate gland - what would urologists like to know from radiologists?] / Die Vorsteherdrüse ­ was möchte der Urologe vom Radiologen wissen?

A more than 100-year period, where the prostate was only seen and treated as a whole is coming to an end right now. Finally, high resolution imaging is providing deep insights and detailed information so that new therapeutic procedures can aim for the smallest targets within the gland. The long-standing wish of patients for individual noninvasive diagnostics and treatment of prostate diseases can now be fulfilled by providing new tailored concepts; however, in order to transfer the enormous amount of new information into the specific clinical patient situation, a closely knit interdisciplinary approach is required. In this setting, the traditional outpatient consultation service is overstretched in every aspect. It is now the time for new innovative constructs. The current one-sided service concept for urologists, radiologists and radiation therapists is therefore behind the times and the development of a "prostate management team" with equally cooperating partners from each specialty is the task for the future.

Radioablation of adrenal gland malignomas with interstitial high-dose-rate brachytherapy : Efficacy and outcome.

PURPOSE: To assess the efficacy, safety, and outcome of image-guided high-dose-rate (HDR) brachytherapy in patients with adrenal gland metastases (AGM). MATERIALS AND METHODS: From January 2007 to April 2014, 37 patients (7 female, 30 male; mean age 66.8 years, range 41.5-82.5 years) with AGM from different primary tumors were treated with CT-guided HDR interstitial brachytherapy (iBT). Primary endpoint was local tumor control (LTC). Secondary endpoints were time to untreatable progression (TTUP), time to progression (TTP), overall survival (OS), and safety. In a secondary analysis, risk factors with an influence on survival were identified. RESULTS: The median biological equivalent dose (BED) was 37.4 Gy. Mean LTC after 12 months was 88%; after 24 months this was 74%. According to CTCAE criteria, one grade 3 adverse event occurred. Median OS after first diagnosis of AGM was 18.3 months. Median OS, TTUP, and TTP after iBT treatment were 11.4, 6.6, and 3.5 months, respectively. Uni- and multivariate Cox regression analyses revealed significant influences of synchronous disease, tumor diameter, and the total number of lesions on OS or TTUP or both. CONCLUSION: Image-guided HDR-iBT is safe and effective. Treatment- and primary tumor-independent features influenced survival of patients with AGM after HDR-iBR treatment.

[MRI/TRUS fusion-guided prostate biopsy : Value in the context of focal therapy]. / MRT/TRUS-fusionierte Biopsiesysteme : Stellenwert bei der fokalen Therapie des Prostatakarzinoms.

BACKGROUND: Several systems for MRI/TRUS fusion-guided biopsy of the prostate are commercially available. Many studies have shown superiority of fusion systems for tumor detection and diagnostic quality compared to random biopsy. The benefit of fusion systems in focal therapy of prostate cancer (PC) is less clear. OBJECTIVES: Critical considerations of fusion systems for planning and monitoring of focal therapy of PC were investigated. MATERIALS AND METHODS: A systematic literature review of available fusion systems for the period 2013-5/2016 was performed. A checklist of technical details, suitability for special anatomic situations and suitability for focal therapy was established by the German working group for focal therapy (Arbeitskreis fokale und Mikrotherapie). RESULTS: Eight fusion systems were considered (Artemis™, BioJet, BiopSee®, iSR´obot™ Mona Lisa, Hitachi HI-RVS, UroNav and Urostation®). Differences were found for biopsy mode (transrectal, perineal, both), fusion mode (elastic or rigid), navigation (image-based, electromagnetic sensor-based or mechanical sensor-based) and space requirements. DISCUSSION: Several consensus groups recommend fusion systems for focal therapy. Useful features are "needle tracking" and compatibility between fusion system and treatment device (available for Artemis™, BiopSee® and Urostation® with Focal One®; BiopSee®, Hitachi HI-RVS with NanoKnife®; BioJet, BiopSee® with cryoablation, brachytherapy). CONCLUSIONS: There are a few studies for treatment planning. However, studies on treatment monitoring after focal therapy are missing.

Why we should not routinely apply irreversible electroporation as an alternative curative treatment modality for localized prostate cancer at this stage.

Irreversible electroporation (IRE), a new tissue ablation procedure available since 2007, could meet the requirements for ideal focal therapy of prostate cancer with its postulated features, especially the absence of a thermal ablation effect. Thus far, there is not enough evidence of its effectiveness or adverse effects to justify its use as a definitive treatment option for localized prostate cancer. Moreover, neither optimal nor individual treatment parameters nor uniform endpoints have been defined thus far. No advantages over established treatment procedures have as yet been demonstrated. Nevertheless, IRE is now being increasingly applied for primary prostate cancer therapy outside clinical trials, not least through active advertising in the lay press. This review reflects the previous relevant literature on IRE of the prostate or prostate cancer and shows why we should not adopt IRE as a routine treatment modality at this stage.

[Focal therapy for small renal masses : Observation, ablation or surgery]. / Fokale Therapie von kleinen Nierentumoren : Beobachtung, Ablation oder Operation.

BACKGROUND: The rising incidence of renal cell carcinoma, its more frequent early detection (stage T1a) and the increasing prevalence of chronic renal failure with higher morbidity and shorter life expectancy underscore the need for multimodal focal nephron-sparing therapy. DISCUSSION: During the past decade, the gold standard shifted from radical to partial nephrectomy. Depending on the surgeon's experience, the patient's constitution and the tumor's location, the intervention can be performed laparoscopically with the corresponding advantages of lower invasiveness. A treatment alternative can be advantageous for selected patients with high morbidity and/or an increased risk of complications associated with anesthesia or surgery. Corresponding risk stratification necessitates previous confirmation of the small renal mass (cT1a) by histological examination of biopsy samples. Active surveillance represents a controlled delay in the initiation of treatment. RESULTS: Percutaneous radiofrequency ablation (RFA) and laparoscopic cryoablation are currently the most common treatment alternatives, although there are limitations particularly for renal tumors located centrally near the hilum. More recent ablation procedures such as high intensity focused ultrasound (HIFU), irreversible electroporation, microwave ablation, percutaneous stereotactic ablative radiotherapy and high-dose brachytherapy have high potential in some cases but are currently regarded as experimental for the treatment of renal cell carcinoma.

Follow-up after focal therapy in renal masses: an international multidisciplinary Delphi consensus project.

PURPOSE: To establish consensus on follow-up (FU) after focal therapy (FT) in renal masses. To formulate recommendations to aid in clinical practice and research. METHODS: Key topics and questions for consensus were identified from a systematic literature research. A Web-based questionnaire was distributed among participants selected based on their contribution to the literature and/or known expertise. Three rounds according to the Delphi method were performed online. Final discussion was conducted during the "8th International Symposium on Focal Therapy and Imaging in Prostate and Kidney Cancer" among an international multidisciplinary expert panel. RESULTS: Sixty-two participants completed all three rounds of the online questionnaire. The panel recommended a minimum follow-up of 5 years, preferably extended to 10 years. The first FU was recommended at 3 months, with at least two imaging studies in the first year. Imaging was recommended biannually during the second year and annually thereafter. The panel recommended FU by means of CT scan with slice thickness ≤3 mm (at least three phases with excretory phase if suspicion of collecting system involvement) or mpMRI. Annual checkup for pulmonary metastasis by CT thorax was advised. Outside study protocols, biopsy during follow-up should only be performed in case of suspicion of residual/persistent disease or radiological recurrence. CONCLUSIONS: The consensus led to clear FU recommendations after FT of renal masses supported by a multidisciplinary expert panel. In spite of the low level of evidence, these recommendations can guide clinicians and create uniformity in the follow-up practice and for clinical research purposes.

[Irreversible electroporation. Current value for focal treatment of prostate cancer]. / Irreversible Elektroporation. Aktueller Stellenwert in der fokalen Therapie des Prostatakarzinoms.

BACKGROUND: Irreversible electroporation (IRE), a new tissue ablation procedure available since 2007, could meet the requirements for ideal focal therapy (FT) with its postulated features, especially the absence of a thermal ablative effect. Thus far, there is no adequate tumor-entity-specific proof of its effectiveness, and its clinical application has hitherto been confined to very small patient cohorts. This also holds true for prostate cancer (PCA). Nevertheless, it is now being increasingly applied outside clinical trials-to a certain extent due to active advertising in the lay press. AIM OF THE STUDY: In this study, current discrepancies between the clinical application and study situation and the approval and market implementation of the procedure are described. The media portrayal of IRE is discussed from different perspectives, particularly with reference to the FT of PCA. This is followed by a final clinical assessment of IRE using the NanoKnife® system. DISCUSSION: Strict requirements govern new drug approvals. According to the German Drug Act (AMG), evidence of additional benefit over existing therapy must be provided through comparative clinical trials. For medicotechnical treatment procedures, on the other hand, such trial-based proof is not required according to the Medical Devices Act (MPG). The use of IRE even outside clinical trials has been actively promoted since the NanoKnife® system was put on the market. This has led to an increase in the number of uncontrolled IRE treatments of PCA in the last 2 years. The patients have to cover the high treatment costs themselves in these cases. If articles in the lay press advertise the procedure with promising but unverified contents, false hopes are raised in those concerned. This is disastrous if it delays the use of truly effective treatment options. CONCLUSION: IRE basically still has high potential for the treatment of malignancies; however, whether it can really be used for FT remains unclear due to the lack of data. This also holds true for the treatment of PCA. Only carefully conducted scientific research studies can clarify the unresolved issues regarding IRE of PCA. The urgently needed development of universally valid treatment standards for IRE is unnecessarily hampered by the flow commercially driven patients.

A prospective Phase 2a pilot study investigating focal percutaneous irreversible electroporation (IRE) ablation by NanoKnife in patients with localised renal cell carcinoma (RCC) with delayed interval tumour resection (IRENE trial).

INTRODUCTION: Focal ablation therapy is playing an increasing role in oncology and may reduce the toxicity of current surgical treatments while achieving adequate oncological benefit. Irreversible electroporation (IRE) has been proposed to be tissue-selective with potential advantages compared with current thermal-ablation technologies or radiotherapy. The aim of this pilot trial is to determine the effectiveness and feasibility of focal percutaneous IRE in patients with localised renal cell cancer as a uro-oncological tumour model. METHODS: Prospective, monocentric Phase 2a pilot study following current recommendations, including those of the International Working Group on Image-Guided Tumor Ablation. Twenty patients with kidney tumour (T1aN0M0) will be recruited. This sample permits an appropriate evaluation of the feasibility and effectiveness of image-guided percutaneous IRE ablation of locally confined kidney tumours as well as functional outcomes. Percutaneous biopsy for histopathology will be performed before IRE, with magnetic-resonance imaging one day before and 2, 7, 27 and 112 days after IRE; at 28 days after IRE the tumour region will be completely resected and analysed by ultra-thin-layer histology. DISCUSSION: The IRENE study will investigate over a short-term observation period (by magnetic-resonance imaging, post-resection histology and assessment of technical feasibility) whether focal IRE, as a new ablation procedure for soft tissue, is feasible as a percutaneous, tissue-sparing method for complete ablation and cure of localised kidney tumours. Results from the kidney-tumour model can provide guidance for designing an effectiveness and feasibility trial to assess this new ablative technology, particularly in uro-oncology.

[Cancer control in focus insights and future perspectives for the focal treatment of prostate cancer]. / Krebskontrolle im Fokus - Einblicke und Ausblicke rund um die fokale Therapie des Prostatakrebses.

Faced with the dilemma of choosing between the extremes of standard whole gland therapy and active surveillance, those affected by prostate cancer have recently been on the lookout for less invasive alternatives. Particularly the question of whether it would be possible in low risk cancer to treat only the tumour itself while sparing the organ has long been considered. This article discusses the pros and cons of focal treatment and elucidates the latest innovative technologies. High overtreatment rates in low-risk patients submitted to standard therapy and considerable technological advances in diagnosis (particularly multiparametric MRI) and therapy are regarded by the authors as key arguments for abandoning complete tumour eradication with its side effects in favour of sufficient local cancer control by focal treatment with better preserved quality of life in suitable cases.

[Surgery of inferior vena cava-associated urological tumor lesions]. / Operative Versorgung V.-cava-inferior-assoziierter urologischer Tumorerkrankungen.

BACKGROUND: Tumor lesions of the inferior vena cava are extremely challenging with regard to adequate therapeutic management also in advanced malignant urological tumor lesions which can be caused by malignant adhesion, impression and tumor infiltration from the surrounding tissue. This can be the case with metastases from a seminoma or testicular carcinoma (differential diagnosis: primary vena cava leiomyosarcoma), tumor-associated growth into and within the inferior vena cava originating from renal cell carcinoma or carcinoma of the pararenal gland. The aim of this overview was to summarize current clinical and operative experiences in the treatment of inferior vena cava-associated urological tumor lesions, perioperative management, individual-specific and finding-adapted surgical technique and possible outcome, including prognostic considerations from clinical daily practice and representative data found in the literature. BASIC STATEMENTS: The primary aim of the surgical approach is to achieve R0 resection with reconstruction of the inferior vena cava lumen providing a reasonable risk-benefit ratio, which comprises i) complete resection and substitution of the inferior vena cava by a prosthesis along the previous extent of tumor growth, ii) partial resection of the vena cava wall with subsequent patch-plasty or tangential resection with primary suture or iii) removal of the vena cava thrombus after cavotomy. Particular attention should be paid to tumor thrombi reaching the right atrium which need to be extracted after sternotomy and atriotomy using an extracorporeal circulation (cardiac surgeon). For surgical planning, subdivision of the inferior vena cava into three segments, infracardiac, infrahepatic and infrarenal third, has been proven and tested. CONCLUSIONS: The current development status and advances in surgical approaches as well as advances in medical technology allow the successful approach to such advanced stage urological tumor manifestations. A deciding factor is the abdominal and cardiovascular surgical expertise of each surgeon after formation of a team of surgical specialists (including urologists) and only then prognostic advantages can be achieved.

[High-intensity focussed ultrasound in low-risk prostate cancer - oncological outcome and postinterventional quality of life of an inexperienced therapy centre in comparison with an experienced therapy centre]. / Hochintensiver fokussierter Ultraschall bei Low-Risk Prostatakarzinom - Onkologisches Outcome und postinterventionelle Lebensqualität im direkten Vergleich eines erfahrenen und unerfahrenen Therapiezentrums.

BACKGROUND: In patients with low-risk prostate cancer (PCa) the standard therapies carry a risk of overtreatment with potentially preventable side effects whereas restrained therapeutic strategies pose a risk of underestimation of the individual cancer risk. Alternative treatment options include thermal ablation strategies such as high-intensity focused ultrasound (HIFU). PATIENTS AND METHODS: 96 patients with low-risk PCa (D'Amico) were treated at 2 HIFU centres with different expertise (n=48, experienced centre Lyon/France; n=48 inexperienced centre Charité Berlin/Germany). Matched pairs were formed and analysed with regard to biochemical disease-free survival (BDFS) as well as postoperative functional parameters (micturition, erectile function). The matched pairs were discriminated as to whether they had received HIFU treatment alone or a combination of HIFU with transurethral resection of the prostate (TURP). Patients of the Lyon group were retrospectively matched through the @-registry database whereas patients of the Berlin group were prospectively evaluated. In the latter patients quality of life assessment was additionally inquired. RESULTS: Postoperative PSA-Nadir was lower in the Berlin group for patients with HIFU only (0.007 vs. Lyon 0.34 ng/ml; p=0.037) and HIFU+TURP (0.25 vs. Lyon 0.42 ng/ml; p=0.003). BDFS was comparable in both groups for HIFU only (Berlin 4.77, Lyon 5.23 years; p=0.741) but patients with combined HIFU+TURP in the Berlin group showed an unfavourable BDFS as compared to the Lyon group (Berlin 3.02, Lyon 4.59 years; p=0.05). In an analysis of Berlin subgroups especially patients who had received HIFU and TURP (n=4) within the same narcosis had an unfavourable BDFS (p=0.009). Median follow-up was 3.36 years for HIFU only and 2.26 years for HIFU+TURP. Neither HIFU only (p=0.117) nor HIFU+TURP (p=0.131) showed an impact on postoperative micturition. Erectile function was negatively influenced (HIFU: p=0.04; HIFU+TURP: p=0.036). There was no measurable change in quality of life after the treatment. CONCLUSION: The 4-year BDFS after HIFU and HIFU+TURP is comparable to that of the standard therapies. The erectile function is sustainably negatively influenced whereas postoperative micturition and quality of life were not affected by HIFU or HIFU+TURP. These results are strongly limited by the low patient count and the short follow-up period and require validation in prospective multicentre studies with higher number of cases.

Kidney dislocation in a monstrous inguinal intestinal hernia with ureteropelvic junction obstruction and acute on chronic renal failure.

INTRODUCTION: Inguinal hernias are the most common hernias in adult males. Abnormalities should be taken into account for therapeutic procedures. This is the first report of a dislocation of a primary orthotopic kidney in a monstrous inguinal intestinal hernia. CASE PRESENTATION: This paper reports an incidental finding of a dislocation of a primary orthotopic kidney in a monstrous inguinal intestinal hernia of an 82-year-old patient with intracranial injury and acute kidney failure. Post-renal kidney failure could be excluded by ultrasound and CT examination. The acute renal decompensation resulted from rhabdomyolysis associated with a falling down trauma with crush syndrome and pneumonic septicaemia based on chronic renal failure associated with nephrosclerosis and ureteropelvic junction obstruction conditioned atrophic right kidney. CONCLUSION: Previous reports in the literature include inguinal-scrotal hernias containing ureter and bladder with post-renal failure or containing ectopic congenital pelvic or transplanted iliac kidney. Our patient is very unusual in that he presented with inguinal herniated, orthotopic, atrophic hydronephrosis with suspicion of congenital ureteropelvic junction obstruction as well as an asymptomatic large intestinal hernia. Reasons for pre-renal acute on chronic renal failure can make it difficult to arrive at a decision of a urological therapy.

Short- and mid-term effects of irreversible electroporation on normal renal tissue: an animal model.

PURPOSE: Irreversible electroporation (IRE) is a novel nonthermal tissue ablation technique by high current application leading to apoptosis without affecting extracellular matrix. Previous results of renal IRE shall be supplemented by functional MRI and differentiated histological analysis of renal parenchyma in a chronic treatment setting. METHODS: Three swine were treated with two to three multifocal percutaneous IRE of the right kidney. MRI was performed before, 30 min (immediate-term), 7 days (short-term), and 28 days (mid-term) after IRE. A statistical analysis of the lesion surrounded renal parenchyma intensities was made to analyze functional differences depending on renal part, side and posttreatment time. Histological follow-up of cortex and medulla was performed after 28 days. RESULTS: A total of eight ablations were created. MRI showed no collateral damage of surrounded tissue. The highest visual contrast between lesions and normal parenchyma was obtained by T2-HR-SPIR-TSE-w sequence of DCE-MRI. Ablation zones showed inhomogeneous necroses with small perifocal edema in the short-term and sharp delimitable scars in the mid-term. MRI showed no significant differences between adjoined renal parenchyma around ablations and parenchyma of untreated kidney. Histological analysis demonstrated complete destruction of cortical glomeruli and tubules, while collecting ducts, renal calyxes, and pelvis of medulla were preserved. Adjoined kidney parenchyma around IRE lesions showed no qualitative differences to normal parenchyma of untreated kidney. CONCLUSIONS: This porcine IRE study reveals a multifocal renal ablation, while protecting surrounded renal parenchyma and collecting system over a mid-term period. That offers prevention of renal function ablating centrally located or multifocal renal masses.

[Magnetic resonance urography in pediatric urology]. / Magnetresonanzurographie in der Kinderurologie.

Magnetic resonance urography (MRU) provides high resolution imaging of the urogenital system and the use of paramagnetic contrast agents enables a functional depiction. This review summarizes existing data concerning this diagnostic procedure in pediatric urology. A systematic search and assessment of the literature was performed.A total of 12 studies were reviewed in detail. In mostly small study populations a great heterogeneity concerning methodology, use of comparative examinations and standards of reference was noted. Besides the quality of anatomical imaging, the functional study of renal excretory function and differential renal function was also assessed. Only a few studies performed statistical analyses.The authors' rating of MRU was mostly positive. Due to methodical weaknesses, lack of independent standards of reference and statistical analyses the overall level of evidence was low. Further high quality studies will be necessary to assess the value of MRU for the diagnostic workup in pediatric urology.

[Irreversible electroporation: the new generation of local ablation techniques for renal cell carcinoma]. / Irreversible Elektroporation : Die neue Generation lokaler Ablationsverfahren beim Nierenzellkarzinom.

BACKGROUND: Local ablation techniques are a major focus of current developments in oncology. The primary aim is to retain organs and preserve organ functions without compromising the oncological outcome. METHOD: Irreversible electroporation (IRE) is a novel ablation technique that involves the application of high-voltage pulses to induce cell apoptosis without causing thermal damage to the target tissue or adjacent structures. AIM: First published in 2005 IRE is currently undergoing preclinical and clinical trials in several areas of oncology and the initial results have been promising. The IRE technique could be a significant development in ablation treatment for renal cell carcinoma (RCC) but decisive proof of its effectiveness for local RCC has not yet been provided. This study presents the results of preclinical and initial clinical trials which are discussed and compared with those of other ablation techniques in order to demonstrate the current value of IRE.