Bjoern G Volkmer

Klinikum Kassel, Cassel, Hesse, Germany

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Publications (165)501.42 Total impact

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    ABSTRACT: To evaluate the risk of a second urinary diversion in patients after radical cystectomy and urinary diversion. We retrospectively analyzed the records of 1,614 patients who underwent urinary diversion from January 1986 to March 2009. The primary diversion was: Neobladder in 71.9 % of male, 42.3 % of female patients, conduit in 17.6 %, and 38.6 %, and ureterocutaneostomy in 9.5 and 12.5 % patients, respectively. The outcome of interest was the need for a second urinary diversion. Fifty-one second/third diversions in 48 patients form the study population. The mean time from primary to second diversion was 57 months (range 0 - 286). The indication for cystectomy was oncologic in 28 and non oncologic in 23 patients. Conversions were continent to continent (n=14), incontinent to continent (n=14), continent to incontinent (n=13), incontinent to incontinent (n=10). Twelve patients had tumor recurrence impacting the initial diversion. In 8, abscess necrosis of the diversion or radiogenic damage was the indication. Six patients with renal failure required conversion. All patients with conversion from incontinent to continent had a strong desire to avoid a stoma. Four patients died perioperatively. One patient developed a short bowel syndrome. A second urinary diversion was required in 1,8 % of bladder cancer patients with a heterogenous etiology, while this rate was 25 %, when the underlying disease was non oncological. Only men with apex sparing cystectomy and woman whose bladder had not been removed achieve excellent functional outcomes to later orthotopic reconstruction. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
    The Journal of urology 08/2015; DOI:10.1016/j.juro.2015.08.086 · 4.47 Impact Factor
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    The Journal of Urology 04/2015; 193(4):e252. DOI:10.1016/j.juro.2015.02.1094 · 4.47 Impact Factor
  • J Bauer · A Kahlmeyer · R Stredele · B.G. Volkmer ·
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    ABSTRACT: The therapy of urinary stones in Germany is mostly a domain of hospitals even now. With the introduction of the German diagnosis-related groups (G-DRG) system in the years 2003/2004 an attempt was made to realize an ever-increasing fair representation and remuneration of treatment costs. Simultaneously, a declared target was to transfer all forms of treatment which did not necessitate hospital admission to the outpatient department. Analysis of the D-DRG data on running invoicing from all German hospitals from 2004/2005 to 2012/2013 showed an increase in case numbers of around 12 % with a parallel increase in the volume of revenues of around 37 %. A special feature was a reduction in the proportion of extracorporeal shockwave therapy (ESWL) as inpatient treatment with a parallel increase in the proportion of ureteroscopic and percutaneous interventions.
    Der Urologe 11/2014; 53(12). DOI:10.1007/s00120-014-3720-0 · 0.44 Impact Factor
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    ABSTRACT: Background In an earlier study we demonstrated the feasibility to create tissue engineered venous scaffolds in vitro and in vivo. In this study we investigated the use of tissue engineered constructs for ureteral replacement in a long term orthotopic minipig model. In many different projects well functional ureretal tissue was established using tissue engineering in animals with short-time follow up (12 weeks). Therefore urothelial cells were harvested from the bladder, cultured, expanded in vitro, labelled with fluorescence and seeded onto the autologous veins, which were harvested from animals during a second surgery. Three days after cell seeding the right ureter was replaced with the cell-seeded matrices in six animals, while further 6 animals received an unseeded vein for ureteral replacement. The animals were sacrificed 12, 24, and 48 weeks after implantation. Gross examination, intravenous pyelogram (IVP), H&E staining, Trichrome Masson’s Staining, and immunohistochemistry with pancytokeratin AE1/AE3, smooth muscle alpha actin, and von Willebrand factor were performed in retrieved specimens. Results The IVP and gross examination demonstrated that no animals with tissue engineered ureters and all animals of the control group presented with hydronephrosis after 12 weeks. In the 24-week group, one tissue engineered and one unseeded vein revealed hydronephrosis. After 48 weeks all tissue engineered animals and none of the control group showed hydronephrosis on the treated side. Histochemistry and immunohistochemistry revealed a multilayer of urothelial cells attached to the seeded venous grafts. Conclusions Venous grafts may be a potential source for ureteral reconstruction. The results of so far published ureteral tissue engineering projects reveal data up to 12 weeks after implantation. Even if the animal numbers of this study are small, there is an increasing rate of hydronephrosis revealing failure of ureteral tissue engineering with autologous matrices in time points longer than 3 months after implantation. Further investigations have to prove adequate clinical outcome and appropriate functional long-term results.
    Journal of Negative Results in BioMedicine 11/2014; 13(1):17. DOI:10.1186/1477-5751-13-17 · 1.47 Impact Factor
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    ABSTRACT: To determine the rates of the available urinary diversion options for patients treated with radical cystectomy for bladder cancer in different settings (pioneering institutions, leading urologic oncology centers, and population based). Population-based data from the literature included all patients (n = 7608) treated in Sweden during the period 1964-2008, from Germany (n = 14,200) for the years 2008 and 2011, US patients (identified from National Inpatient Sample during 1998-2005, 35,370 patients and 2001-2008, 55,187 patients), and from Medicare (n = 22,600) for the years 1992, 1995, 1998, and 2001. After the International Consultation on Urologic Diseases-European Association of Urology International Consultation on Bladder Cancer 2012, the urinary diversion committee members disclosed data from their home institutions (n = 15,867), including the pioneering institutions and the leading urologic oncology centers. They are the coauthors of this report. The receipt of continent urinary diversion in Sweden and the United States is <15%, whereas in the German high-volume setting, 30% of patients receive a neobladder. At leading urologic oncology centers, this rate is also 30%. At pioneering institutions up to 75% of patients receive an orthotopic reconstruction. Anal diversion is <1%. Continent cutaneous diversion is the second choice. Enormous variations in urinary diversion exist for >2 decades. Increased attention in expanding the use of continent reconstruction may help to reduce these disparities for patients undergoing radical cystectomy for bladder cancer. Continent reconstruction should not be the exclusive domain of cystectomy centers. Efforts to increase rates of this complex reconstruction must concentrate on better definition of the quality-of-life impact, technique dissemination, and the centralization of radical cystectomy. Copyright © 2014 Elsevier Inc. All rights reserved.
    Urology 11/2014; 85(1). DOI:10.1016/j.urology.2014.06.075 · 2.19 Impact Factor
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    ABSTRACT: Objective To externally validate May et al.'s pT4a-specific risk model for cancer-specific survival (CSS) and to develop a new pT4a-specific nomogram predicting CSS in an international multicentre cohort of patients undergoing radical cystectomy (RC) for urothelial carcinoma of the bladder (UCB)Patients and Methods Data of 856 pT4a patients after RC for UCB at 21 centres in Europe and North-America was assessed.May et al.'s risk model including female gender, presence of positive LVI and lack of AC administration as adverse predictors for CSS was applied to our cohort.For the purpose of external validation, model discrimination was measured using the receiver operating characteristics derived area under the curve.A nomogram for predicting CSS in pT4a UCB after RC was developed after internal validation based on multivariable Cox proportional hazards regression analysis evaluating the impact of clinico-pathological parameters on CSS.Decision curve analyses were applied to determine the net benefit derived from the two models.ResultsThe estimated 5-year-CSS after RC was 34% in our cohort.May et al.'s risk model predicted individual 5-year-CSS with an accuracy of 60.1%.In multivariable Cox proportional hazards regression analysis, female gender (HR1.45), lymphovascular invasion (HR1.37), lymph node metastases (HR2.54), positive soft tissue surgical margin (HR1.39), neoadjuvant (HR2.24) and lack of adjuvant chemotherapy (HR1.67, all p<0.05) were independent predictors of an adverse CSS and formed the features of our nomogram with a predictive accuracy of 67.1%.Decision curve analyses showed higher net benefits for the use of the newly developed nomogram in our cohort over all thresholds.Conclusion May et al.'s risk model was validated with a moderate discrimination and outperformed by our newly developed pT4a-specific nomogram in our study population.Thus, it might be particularly suitable for postoperative patient counselling in the heterogeneous cohort of pT4a UCB.
    BJU International 11/2014; DOI:10.1111/bju.12984 · 3.53 Impact Factor
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    ABSTRACT: Purpose To evaluate the prognostic value of concomitant seminal vesicle invasion (cSVI) in patients with urothelial carcinoma of the bladder (UCB) and contiguous prostatic stromal infiltration in a large cystectomy series. Methods A total of 385 patients with UCB and contiguous prostatic infiltration comprised our study. Patients were divided in two groups according to cSVI. Median follow-up was 36 months (interquartile range 11–74); the primary end point was cancer-specific mortality. The prognostic impact of cSVI was evaluated using multivariable Cox regression analysis. The predictive accuracy was assessed by a receiver operating characteristic analysis. Results A total of 229 patients (59.5 %) without cSVI comprised group A, and 156 patients (40.5 %) with cSVI comprised group B. Positive lymph nodes (63 vs. 44 %, p
    Annals of Surgical Oncology 06/2014; 21(12). DOI:10.1245/s10434-014-3827-y · 3.93 Impact Factor
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    ABSTRACT: To evaluate for the first time the prognostic significance of female invasive patterns in stage pT4a urothelial carcinoma of the bladder in a large series of women undergoing anterior pelvic exenteration. Our series comprised of 92 female patients in total of whom 87 with known invasion patterns were eligible for final analysis. Median follow-up for evaluation of cancer-specific mortality (CSM) was 38 months (interquartile ranges, 21-82 months). The impact on CSM was evaluated using multivariable Cox proportional-hazards regression analysis; predictive accuracy (PA) was assessed by receiver operating characteristic analysis. Vaginal invasion was noted in 33 patients (37.9 %; group VAG), uterine invasion in 20 patients (23 %; group UT), and infiltration of both vagina and uterus in 34 patients (39.1 %; group VAG + UT). Groups VAG and UT significantly differed from group VAG + UT with regard to the presence of positive soft tissue margins (STM) only. Five-year-cancer-specific survival probabilities in the groups VAG, UT, and VAG + UT were 21, 20, and 21 %, respectively (p = 0.955). On multivariable analysis, only STM status (HR = 2.02, p = 0.023) independently influenced CSM. C-indices of multivariable models for CSM with and without integration of invasive patterns were 0.570 and 0.567, respectively (PA gain 0.3 %, p = 0.526). Infiltration of the vagina, the uterus or both is associated with poor 5-year survival rates. With regard to CSM, no difference was detectable between patients with different invasion patterns, thus justifying further collectively including these invasive patterns as stage pT4a.
    World Journal of Urology 05/2014; 33(3). DOI:10.1007/s00345-014-1308-3 · 2.67 Impact Factor
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    ABSTRACT: To determine the association of gender with outcome after radical cystectomy for patients with bladder cancer. An observational cohort study was conducted using retrospectively collected data from 11 centers on patients with advanced bladder cancer treated with radical cystectomy. The association of gender with disease recurrence and cancer-specific mortality was examined using a competing risk analysis. The study comprised 4296 patients, including 890 women (21%). The median follow-up duration was 31.5 months for all patients. Disease recurred in 1430 patients (33.9%) (36.8% of women and 33.1% of men) at a median of 11 months after surgery. Death from any cause was observed in 46.0% of men and 50.1% of women. Cancer-specific death was observed in 33.0% of women and 27.2% of men. Multivariable regression with competing risk found that female gender was associated with an increased risk for disease recurrence and cancer-specific mortality (hazard ratio, 1.27; 95% confidence interval, 1.108-1.465; P = .007) compared with male gender. Important limitations include the inability to account for additional potential confounders, such as differences in environmental exposures, treatment selection, and histologic subtypes between men and women. Our analysis identified female gender as a poor-risk feature for patients undergoing radical cystectomy. This adverse prognostic factor was independent of standard clinical and pathologic features and competing risk from non-cancer-related death.
    Urology 01/2014; 83(4). DOI:10.1016/j.urology.2013.10.060 · 2.19 Impact Factor
  • B.G. Volkmer · A Kahlmeyer · M Petervari · M Pechoel ·
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    ABSTRACT: The objective of the German DRG (diagnosis-related groups) system is to adequately reimburse hospital costs using flat rate payments. The goal is to thereby achieve the most adequate representation of hospital costs in flat rate payments. The DRG for 2014 is based on the actual number of cases treated and the costs determined from 2012. For 2014, the current changes of the DRG system for the specialty urology concerning the coding and recording of secondary diagnoses are presented and discussed.
    Der Urologe 01/2014; 53(1):27-32. DOI:10.1007/s00120-013-3397-9 · 0.44 Impact Factor
  • B.G. Volkmer · A. Kahlmeyer · M. Petervari · M. Pechoel ·
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    ABSTRACT: Das Ziel des deutschen DRG-Systems (German diagnosis-related groups) ist die möglichst adäquate Abbildung der Krankenhauskosten in Fallpauschalen. Die DRG für das Jahr 2014 beruhen auf der Basis der tatsächlich behandelten Fälle und ermittelten Kosten von 2012. Für 2014 werden die aktuellen Veränderungen des DRG-Systems für den Fachbereich Urologie betreffend der Kodierung und Erfassung der Nebendiagnosen dargestellt und diskutiert.
    Der Urologe 01/2014; 53(1). · 0.44 Impact Factor
  • A. Kahlmeyer · B. Volkmer ·
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    ABSTRACT: Die seit 2003 erfolgten permanenten Anpassungen des G-DRG-Systems (,,German diagnosis-related groups“) haben das System immer undurchsichtiger werden lassen, so dass viele Anwender das Gefühl einer ,,black box“ haben, in die sie Daten einspeisen und aus der sie ein Ergebnis erhalten, ohne das System aktiv für sich nutzen zu können. Während Chefärzte, leitende Oberärzte und Pflegedienstleitungen die Resultate der Abrechnung vor der Geschäftsführung verantworten müssen, sind sie jedoch in den meisten Fällen in die Schritte der DRG-Kodierung und der Abrechnung nicht eingebunden. Aus dieser Situation ergibt sich die regelmäßige Frage: ,,Wie gut kodiert meine Abteilung eigentlich?“ Diese Unsicherheit nutzen viele kommerzielle Anbieter und offerieren verschiedenste Ansätze der DRG-Optimierung. Ziel dieser Arbeit soll es sein, Hinweise zu geben, woran sich die Kodierqualität erkennen lässt.
    Der Urologe 01/2014; 53(1). DOI:10.1007/s00120-013-3366-3 · 0.44 Impact Factor
  • A Kahlmeyer · B Volkmer ·
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    ABSTRACT: The permanent adjustments since 2003 to the G-DRG system have made the system even less understandable, so that many users have the feeling of feeding data into a black box which gives them a result without them being able to actively use the system itself. While chief physicians, senior physicians, and nursing managers are responsible to management for the results of the billing, they are in most cases not involved in the steps of DRG coding and billing. From this situation, a common question arises: "How well does my department code?" This uncertainty is exploited by many commercial vendors, who offer a wide variety of approaches for DRG optimization. The goal of this work is to provide advice as to how coding quality can be determined.
    Der Urologe 01/2014; 53(1):33-40. · 0.44 Impact Factor
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    ABSTRACT: Here we report the discovery of truncating mutations of the gene encoding the cohesin subunit STAG2, which regulates sister chromatid cohesion and segregation, in 36% of papillary non-invasive urothelial carcinomas and 16% of invasive urothelial carcinomas of the bladder. Our studies suggest that STAG2 plays a role in controlling chromosome number but not proliferation of bladder cancer cells. These findings identify STAG2 as among the most commonly mutated genes in bladder cancer discovered to date.
    Nature Genetics 10/2013; 45(12). DOI:10.1038/ng.2800 · 29.35 Impact Factor
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    ABSTRACT: Expression of T-cell co-regulatory proteins has been associated with worse outcomes in patients with UCB. We aimed to confirm these findings. The study comprised tissue microarrays from 302 consecutive UCB patients treated with RC and lymphadenectomy between 1988 and 2003, 117 matched lymph nodes, and 50 cases of adjacent normal urothelium controls, which were evaluated for B7-H1, B7-H3, and PD-1 protein expression by immunohistochemistry. B7-H3 and PD-1 expression were increased in cancers compared to adjacent normal urothelium (58.6% vs 6% and 65% vs 0%, respectively; both p values < 0.001). Meanwhile, B7-H1 was expressed in 25% of cancers (n = 76). Expression of B7-H3, B7-H1, and PD-1 were highly correlated between the primary tumors and metastatic nodes, with concordance rates of 90%, 86%, and 78% for B7H3, B7H1 and PD-1, respectively. Expression was not associated with clinicopathologic features, disease recurrence, cancer-specific or overall mortality. However, for the subgroup of patients with organ-confined disease (n = 96), B7-H1 expression was associated with an increased risk of overall mortality (p = 0.02) on univariate and trended toward an association on multivariate analyses (p = 0.06). B7-H1, B7-H3 and PD-1 are altered in a large proportion of UCB. B7-H1 and PD-1 expression are differentially upregulated in cancer versus normal urothelium. High correlation between expression in LN and expression in RC specimens was observed. While expression was not associated with clinicopathologic features or standard outcomes in all patients, B7-H1 expression predicted overall mortality after RC in the subset of patients with organ-confined UCB.
    European journal of surgical oncology: the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology 09/2013; 40(1). DOI:10.1016/j.ejso.2013.08.023 · 3.01 Impact Factor
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    ABSTRACT: Oncofetal proteins are expressed in the developing embryo. Oncofetal protein expression has been correlated to clinical outcome in non-muscle-invasive UCB. IMP3, MAGE-A, glypican-3 and TPBG are oncofetal proteins that have not been well characterized in UCB. We investigated the expression of these four proteins and their association with clinical outcomes using tissue microarrays from 384 consecutive patients treated with radical cystectomy between 1988 and 2003 at one academic center. We stained for IMP3, MAGE-A, glypican-3, and TPBG. Uni/Multivariable Cox-regression analyses evaluated the association of oncofetal protein expression with disease recurrence and cancer-specific mortality. IMP3, MAGE-A, glypican-3, and TPBG were expressed in 39.5%, 45%, 6%, and 85% of UCB, respectively. Their expression was tumor-specific and not correlated to pathological features, except for TPBG. With a median follow-up of 128 months, 176 patients (46%) experienced disease recurrence, 175 (45.5%) died of the disease, and 96 (27.5%) died of other causes. In univariable analyses, IMP3 and MAGE-A expression were associated with an increased risk of disease recurrence (p<0.001 and p=0.03, respectively) and cancer-specific mortality (p=0.004 and p=0.03, respectively). In multivariable Cox regression analyses that adjusted for the effects of standard clinicopathologic features, IMP3 and MAGE-A expression were both independently associated with disease recurrence (p=0.004, HR:1.55, CI:1.15-2.11; p=0.02, HR:1.44, CI: 1.05-1.99, respectively) but not with cancer-specific mortality. Oncofetal proteins are commonly and differentially expressed in UCB compared to normal urothelium. IMP3 and MAGE-A expression were associated with disease recurrence and cancer-specific mortality, while glypican-3 and TPBG were not.
    The Journal of urology 08/2013; 191(3). DOI:10.1016/j.juro.2013.08.048 · 4.47 Impact Factor
  • B Volkmer · A Weber · W Bühmann ·
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    ABSTRACT: In a field of medicine with fluid boundaries between the sectors and between the productive faculties, healthcare research is an indispensible responsibility of all participants. This can only be successful in improving the treatment quality of patients in the long-term by analysis of the treatment reality in routine daily work. This can be achieved by a closer cooperation between urologists in private practice and in hospitals in order to have a better definition of mutual treatment targets, to optimize therapy and to make a better analysis of target achievements. The importance of urologists in all fields of medical care and also for superordinate committees can only be visibly presented by the production of comprehensive objective figures and therefore to guarantee the long-term procurement of necessary resources.
    Der Urologe 08/2013; 52(8). DOI:10.1007/s00120-013-3243-0 · 0.44 Impact Factor
  • Bjoern Volkmer · Karen Czeloth · Regina Stredele · Richard Hautmann ·

    The Journal of Urology 04/2013; 189(4):e580-e581. DOI:10.1016/j.juro.2013.02.2772 · 4.47 Impact Factor

  • The Journal of Urology 04/2013; 189(4):e462-e463. DOI:10.1016/j.juro.2013.02.747 · 4.47 Impact Factor
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    ABSTRACT: BACKGROUND: Cabazitaxel (Cbz) is an approved second-line treatment in metastatic castration-resistant prostate cancer (mCRPC) following docetaxel therapy with a significant survival benefit compared with mitoxantrone. However, grade 3/4 toxicities were reported in 82% of patients. OBJECTIVE: To report on the safety results of mCRPC patients treated within a compassionate-use programme in Germany. DESIGN, SETTING, AND PARTICIPANTS: A total of 111 patients with a mean age of 67.9 yr (range: 49-81 yr) and progressive mCRPC were included. Patients had received a mean number of 12.7±10.8 cycles (range: 6-69 cycles) of docetaxel with a mean cumulative dose of 970.9mg/m(2); mean time from last docetaxel application to progression was 6.95 mo (range: 2-54 mo). Of the patients, 31.5% progressed by prostate-specific antigen (PSA) increase only; the remainder had a combination of PSA increase and clinical progression. INTERVENTION: Cbz at a dosage of 25mg/m(2) intravenously every 3 wk combined with 5mg of oral prednisone twice a day. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Treatment-associated toxicity was the primary study end point; progression-free and overall survival were secondary end points. A descriptive statistical analysis was performed. RESULTS AND LIMITATIONS: Patients received a mean number of 6.5±2.2 cycles of Cbz and a mean cumulative dose of 160.3±51.5mg/m(2). Grade 3 and 4 treatment-emergent adverse events were recorded in 34 patients (30.6%) and 18 patients (16.2%), respectively. Grade 3/4 anaemia, neutropenia, and thrombocytopenia were reported in 4.5%, 7.2%, and 0.9% of the patients, respectively. Neutropenic fever was reported in 1.8% of the patients. Grade 3/4 gastrointestinal toxicity was identified in 4.5% of the patients. Three patients died because of Cbz-related toxicity. Granulocyte colony-stimulating growth factors were used in 17.1% of patients. The limitations are due to the nonrandomised nature of the trial. CONCLUSIONS: Treatment with Cbz is tolerable and is associated with a low incidence of serious adverse events in a real-world patient population with CRPC. The outcome of serious adverse events can be minimised with proactive treatment management and conscientious monitoring.
    European Urology 09/2012; 63(6). DOI:10.1016/j.eururo.2012.08.058 · 13.94 Impact Factor

Publication Stats

3k Citations
501.42 Total Impact Points


  • 2009-2015
    • Klinikum Kassel
      Cassel, Hesse, Germany
  • 2002-2012
    • Universität Ulm
      • Faculty of Medicine
      Ulm, Baden-Württemberg, Germany
  • 2008
    • University of Tuebingen
      Tübingen, Baden-Württemberg, Germany
  • 2006
    • Universitätsklinikum Schleswig - Holstein
      • Klinik für Urologie und Kinderurologie (Kiel)
      Kiel, Schleswig-Holstein, Germany