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6.
World J Urol ; 39(1): 89-95, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32236662

ABSTRACT

OBJECTIVES: To investigate the predictors of recurrence and of de novo incontinence in patients treated by transurethral incision or resection for vesico-urethral anastomotic stenosis (VUAS) after radical prostatectomy. MATERIAL AND METHODS: All patients undergoing endoscopic treatment for VUAS between March 2009 and October 2016 were identified in our multi-institutional database. Digital chart reviews were performed and patients contacted for follow-up. Recurrence was defined as any need for further instrumentation or surgery, and de-novo-incontinence as patient-reported outcome. RESULTS: Of 103 patients undergoing endoscopic VUAS treatment, 67 (65%) underwent transurethral resection (TR) and 36 (35%) transurethral incision (TI). TI was performed more frequently as primary treatment compared to TR (58% vs. 37%; p = 0.041). Primary and repeated treatment was performed in 46 (45%) and 57 patients (55%), respectively. Overall, 38 patients (37%) had a history of radiation therapy. There was no difference in time to recurrence for primary vs repeat VUAS treatment, previous vs no radiation, TR compared to TI (all p > 0.08). Regarding treatment success, no difference was found for primary vs. repeat VUAS treatment (50% vs. 37%), previous radiation vs. no radiation (42% vs. 43%), and TR vs. TI (37% vs. 53%; all p ≥ 0.1). Postoperative de novo incontinence was more common after TI vs. TR (31% vs. 12%; p = 0.032), no difference was observed for previous radiation therapy vs. no radiation therapy (18% vs. 18%; p > 0.9) or primary vs. repeat VUAS treatment (22% vs. 16%; p = 0.5). CONCLUSION: VUAS recurrence after endoscopic treatment is not predictable. Endoscopic treatment with TI showed a higher risk for de novo incontinence than TR, and previous irradiation and the number of treatments do not influence incontinence.


Subject(s)
Postoperative Complications/surgery , Prostatectomy , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Urethra/surgery , Urethral Stricture/surgery , Urinary Bladder/surgery , Aged , Anastomosis, Surgical , Constriction, Pathologic , Endoscopy , Humans , Male , Prostatectomy/methods , Retrospective Studies , Treatment Outcome
7.
Article in English | MEDLINE | ID: mdl-32217475

ABSTRACT

Shear-wave elastography (SWE) permits local estimation of tissue elasticity, an important imaging marker in biomedicine. This recently developed, advanced technique assesses the speed of a laterally traveling shear wave after an acoustic radiation force "push" to estimate local Young's moduli in an operator-independent fashion. In this work, we show how synthetic SWE (sSWE) images can be generated based on conventional B-mode imaging through deep learning. Using side-by-side-view B-mode/SWE images collected in 50 patients with prostate cancer, we show that sSWE images with a pixel-wise mean absolute error of 4.5 ± 0.96 kPa with regard to the original SWE can be generated. Visualization of high-level feature levels through t -distributed stochastic neighbor embedding reveals substantial overlap between data from two different scanners. Qualitatively, we examined the use of the sSWE methodology for B-mode images obtained with a scanner without SWE functionality. We also examined the use of this type of network in elasticity imaging in the thyroid. Limitations of the technique reside in the fact that networks have to be retrained for different organs, and that the method requires standardization of the imaging settings and procedure. Future research will be aimed at the development of sSWE as an elasticity-related tissue typing strategy that is solely based on B-mode ultrasound acquisition, and the examination of its clinical utility.


Subject(s)
Deep Learning , Elasticity Imaging Techniques/methods , Image Processing, Computer-Assisted/methods , Humans , Thyroid Gland/diagnostic imaging
8.
Article in English | MEDLINE | ID: mdl-32091998

ABSTRACT

Blind source separation (BSS) refers to a number of signal processing techniques that decompose a signal into several "source" signals. In recent years, BSS is increasingly employed for the suppression of clutter and noise in ultrasonic imaging. In particular, its ability to separate sources based on measures of independence rather than their temporal or spatial frequency content makes BSS a powerful filtering tool for data in which the desired and undesired signals overlap in the spectral domain. The purpose of this work was to review the existing BSS methods and their potential in ultrasound imaging. Furthermore, we tested and compared the effectiveness of these techniques in the field of contrast-ultrasound super-resolution, contrast quantification, and speckle tracking. For all applications, this was done in silico, in vitro, and in vivo. We found that the critical step in BSS filtering is the identification of components containing the desired signal and highlighted the value of a priori domain knowledge to define effective criteria for signal component selection.

9.
Urologe A ; 58(12): 1443-1450, 2019 Dec.
Article in German | MEDLINE | ID: mdl-31741002

ABSTRACT

Initial clinical and pathological diagnostic workup of urinary bladder cancer is based on cystoscopy, transurethral resection of suspicious lesions, and computed tomography when indicated. Accurate staging is necessary for further therapeutic decision-making. This review summarizes the current status of multiparametric magnetic resonance imaging (mpMRI) and the vesical imaging-reporting and data system (VI-RADS) classification. MpMRI may improve the accuracy of assessment of local tumor invasion compared to conventional imaging alone. VI-RADS standardizes reporting of MRI staging and classifies the likelihood of muscle-invasive bladder cancer into five categories. Preliminary data suggest low interobserver variability. However, prospective multicenter studies are necessary to validate the VI-RADS classification. Progress in functional, molecular, and hybrid imaging may further improve the accuracy of clinical tumor and nodal staging for bladder cancer.


Subject(s)
Data Systems , Urinary Bladder Neoplasms , Humans , Magnetic Resonance Imaging , Male , Neoplasm Invasiveness , Prospective Studies , Urinary Bladder Neoplasms/diagnostic imaging
10.
Urologe A ; 58(5): 569-582, 2019 May.
Article in German | MEDLINE | ID: mdl-31049635

ABSTRACT

Following definitive treatment with curative intent a subset of patients with prostate cancer experience biochemical recurrence. In these patients clinical parameters are mostly used to decide if a local or systemic disease recurrence is present. While salvage radiation treatment is advocated for local recurrence after radical prostatectomy, no standard recommendations exist in cases of local recurrence after primary radiation therapy although salvage prostatectomy may be considered. Imaging procedures have traditionally not routinely been recommended for the onset of prostate-specific antigen (PSA) relapse; however, prostate-specific membrane antigen (PSMA) positron emission tomography (PET) computed tomography (CT) exhibits high detection rates even at low PSA values. Thus, the current German guidelines state that PSMA PET/CT can be considered if this could result in a decisive change in further treatment management. Currently, a positive influence on oncological long-term outcome, however, has not yet been proven.


Subject(s)
Antigens, Surface/metabolism , Glutamate Carboxypeptidase II/metabolism , Positron Emission Tomography Computed Tomography , Positron-Emission Tomography , Practice Guidelines as Topic , Prostatic Neoplasms/diagnostic imaging , Germany , Humans , Male , Neoplasm Recurrence, Local , Prostate-Specific Antigen/blood , Prostatectomy
11.
Urologe A ; 58(5): 494-503, 2019 May.
Article in German | MEDLINE | ID: mdl-30874832

ABSTRACT

The initial diagnosis of prostate cancer has been traditionally performed using systematic core biopsies with the use of magnetic resonance imaging (MRI) reserved to problem-solving scenarios. There is currently an ongoing paradigm shift towards the use of MRI prior to targeted biopsy as the standard approach. Prostate cancer therefore does not remain the last solid tumor entity diagnosed by non-targeted techniques but joins other solid tumor entities for which targeted diagnostic approaches have existed for a while. However, the complexity of the background tissue signal in the prostate makes lesion detection challenging. This article will provide an overview of the components of multiparametric prostate MRI and their interpretation using structured interpretation according to the current PI-RADSv2 (Prostate Imaging Reporting and Data System version 2) guidelines and of novel ultrasound techniques for primary diagnosis.


Subject(s)
Magnetic Resonance Imaging/methods , Prostatic Neoplasms/diagnostic imaging , Ultrasonography, Interventional , Humans , Male
13.
Malar J ; 17(1): 156, 2018 Apr 06.
Article in English | MEDLINE | ID: mdl-29625574

ABSTRACT

BACKGROUND: In 2011, the demographic and health survey (DHS) in Cameroon was combined with the multiple indicator cluster survey. Malaria parasitological data were collected, but the survey period did not overlap with the high malaria transmission season. A malaria indicator survey (MIS) was also conducted during the same year, within the malaria peak transmission season. This study compares estimates of the geographical distribution of malaria parasite risk and of the effects of interventions obtained from the DHS and MIS survey data. METHODS: Bayesian geostatistical models were applied on DHS and MIS data to obtain georeferenced estimates of the malaria parasite prevalence and to assess the effects of interventions. Climatic predictors were retrieved from satellite sources. Geostatistical variable selection was used to identify the most important climatic predictors and indicators of malaria interventions. RESULTS: The overall observed malaria parasite risk among children was 33 and 30% in the DHS and MIS data, respectively. Both datasets identified the Normalized Difference Vegetation Index and the altitude as important predictors of the geographical distribution of the disease. However, MIS selected additional climatic factors as important disease predictors. The magnitude of the estimated malaria parasite risk at national level was similar in both surveys. Nevertheless, DHS estimates lower risk in the North and Coastal areas. MIS did not find any important intervention effects, although DHS revealed that the proportion of population with an insecticide-treated nets access in their household was statistically important. An important negative relationship between malaria parasitaemia and socioeconomic factors, such as the level of mother's education, place of residence and the household welfare were captured by both surveys. CONCLUSION: Timing of the malaria survey influences estimates of the geographical distribution of disease risk, especially in settings with seasonal transmission. In countries with different ecological zones and thus different seasonal patterns, a single survey may not be able to identify all high risk areas. A continuous MIS or a combination of MIS, health information system data and data from sentinel sites may be able to capture the disease risk distribution in space across different seasons.


Subject(s)
Cross-Sectional Studies/methods , Demography/methods , Malaria, Falciparum/epidemiology , Parasitemia/epidemiology , Adolescent , Adult , Bayes Theorem , Cameroon/epidemiology , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Logistic Models , Malaria, Falciparum/parasitology , Male , Middle Aged , Parasitemia/parasitology , Plasmodium falciparum/physiology , Prevalence , Risk Assessment , Socioeconomic Factors , Young Adult
14.
Br J Dermatol ; 178(5): 1199-1203, 2018 05.
Article in English | MEDLINE | ID: mdl-29274233

ABSTRACT

Xeroderma pigmentosum (XP) is an orphan disease of poor prognosis. We report one case of parallel efficacy with anti-programmed cell death-1 (PD-1) antibody on both melanoma and skin carcinoma in a patient with XP. A 17-year-old patient presented with metastatic melanoma and multiple nonmelanoma skin cancers. He was treated with pembrolizumab, a monoclonal anti-PD-1 antibody, at a dose of 2 mg kg-1 , every 3 weeks. Parallel therapeutic efficacy of anti-PD-1 was observed in metastatic melanoma and skin carcinomas, and maintained at week 24. This observation suggests anti-PD-1 may be considered in patients with XP and metastatic melanoma in addition to advanced nonmelanoma skin cancer.


Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Antineoplastic Agents, Immunological/administration & dosage , Immunotherapy/methods , Melanoma/drug therapy , Skin Neoplasms/drug therapy , Adolescent , Drug Administration Schedule , Humans , Male , Melanoma/secondary , Neoplasm Metastasis , Programmed Cell Death 1 Receptor/immunology , Treatment Outcome , Xeroderma Pigmentosum/complications
15.
Urologe A ; 56(10): 1335-1346, 2017 Oct.
Article in German | MEDLINE | ID: mdl-28856386

ABSTRACT

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.


Subject(s)
Prostatic Neoplasms/therapy , Biopsy , Brachytherapy , Cryotherapy , Disease Progression , Endosonography , High-Intensity Focused Ultrasound Ablation , Humans , Laser Therapy , Magnetic Resonance Imaging , Male , Neoplasm Grading , Neoplasm Staging , Photochemotherapy , Prognosis , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/pathology , Randomized Controlled Trials as Topic , Sensitivity and Specificity
16.
World J Urol ; 35(5): 695-701, 2017 May.
Article in English | MEDLINE | ID: mdl-27637908

ABSTRACT

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.


Subject(s)
Magnetic Resonance Imaging , Prostatic Neoplasms/diagnostic imaging , Ablation Techniques , Biopsy , Cryosurgery , Delphi Technique , Electrochemotherapy , High-Intensity Focused Ultrasound Ablation , Humans , Laser Therapy , Male , Pathologists , Photochemotherapy , Prostatic Neoplasms/pathology , Prostatic Neoplasms/therapy , Radiologists , Surveys and Questionnaires , Urologists
17.
Urologe A ; 56(2): 208-216, 2017 Feb.
Article in German | MEDLINE | ID: mdl-27844131

ABSTRACT

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.


Subject(s)
Endoscopic Ultrasound-Guided Fine Needle Aspiration/instrumentation , Magnetic Resonance Imaging/instrumentation , Multimodal Imaging/instrumentation , Prostatic Neoplasms/pathology , Prostatic Neoplasms/therapy , Equipment Design , Equipment Failure Analysis , Humans , Male , Prostatic Neoplasms/diagnostic imaging , Reproducibility of Results , Sensitivity and Specificity , Technology Assessment, Biomedical
18.
World J Urol ; 35(1): 11-20, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27147512

ABSTRACT

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.


Subject(s)
Ablation Techniques/methods , Electroporation/methods , Prostatic Neoplasms/therapy , Humans , Male , Prostatic Neoplasms/pathology , Treatment Outcome
19.
Urologe A ; 55(5): 594-606, 2016 May.
Article in German | MEDLINE | ID: mdl-27119957

ABSTRACT

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.


Subject(s)
Carcinoma, Renal Cell/surgery , Kidney Neoplasms/surgery , Minimally Invasive Surgical Procedures/methods , Organ Sparing Treatments/methods , Carcinoma, Renal Cell/pathology , Catheter Ablation , Cryosurgery , Humans , Kidney Neoplasms/pathology , Laparoscopy , Neoplasm Staging , Nephrectomy , Watchful Waiting
20.
World J Urol ; 34(10): 1373-82, 2016 Oct.
Article in English | MEDLINE | ID: mdl-26892160

ABSTRACT

PURPOSE: To reach standardized terminology in focal therapy (FT) for prostate cancer (PCa). METHODS: A four-stage modified Delphi consensus project was undertaken among a panel of international experts in the field of FT for PCa. Data on terminology in FT was collected from the panel by three rounds of online questionnaires. During a face-to-face meeting on June 21, 2015, attended by 38 experts, all data from the online rounds were reviewed and recommendations for definitions were formulated. RESULTS: Consensus was attained on 23 of 27 topics; Targeted FT was defined as a lesion-based treatment strategy, treating all identified significant cancer foci; FT was generically defined as an anatomy-based (zonal) treatment strategy. Treatment failure due to the ablative energy inadequately destroying treated tissue is defined as ablation failure. In targeting failure the energy is not adequately applied to the tumor spatially and selection failure occurs when a patient was wrongfully selected for FT. No definition of biochemical recurrence can be recommended based on the current data. Important definitions for outcome measures are potency (minimum IIEF-5 score of 21), incontinence (new need for pads or leakage) and deterioration in urinary function (increase in IPSS >5 points). No agreement on the best quality of life tool was established, but UCLA-EPIC and EORTC-QLQ-30 were most commonly supported by the experts. A complete overview of statements is presented in the text. CONCLUSION: Focal therapy is an emerging field of PCa therapeutics. Standardization of definitions helps to create comparable research results and facilitate clear communication in clinical practice.


Subject(s)
Consensus , Delphi Technique , Prostatic Neoplasms/therapy , Quality of Life , Combined Modality Therapy/standards , Humans , Male , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Surveys and Questionnaires
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