C. Ohlmann

Universität des Saarlandes, Saarbrücken, Saarland, Germany

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Publications (48)153.56 Total impact

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    ABSTRACT: Background: Choline is an important source of phospholipids and methyl groups in mammalian cells. High demands for methyl and phospholipids in malignant cells suggest that choline metabolism may be disturbed in patients with cancer. Objectives and methods: This case-control study investigated differences in concentrations of choline metabolites between 80 elderly men (age ≥ 65 years) with prostate cancer (PCa) and 51 men with benign prostatic hyperplasia (BPH). Plasma/serum concentrations of free choline, betaine, dimethylglycine, folate, total homocysteine (tHcy), cystathionine, methylmalonic acid, S-adenosyl homocysteine (SAH), S-adenosyl methionine (SAM), and phospholipids were measured. Results: Men with BPH and those with PCa showed no significant differences in the concentrations of free choline (median = 9.7 vs. 10.0 μmol/L), folate (17.4 vs. 19.8 nmol/L), tHcy (16.0 vs. 16.2 μmol/L), SAH (18.8 vs. 18.2 nmol/L), and phosphatidylcholine (1634 vs. 1610 μmol/L). The concentrations of methylmalonic acid were lower in men with PCa (203 vs. 228 nmol/L) but the difference was not significant after adjusting for age. Sphingomyelin species (16:0, 18:0, 18:1, 20:0, 22:0, 22;1, 23:0, 23:1, 24:0, 24:1, and 24:2) were significantly lower in men with PCa than in the controls (6-16% differences). Multiple regression analyses showed that the presence of PCa, statin use, choline, age, cystathionine, and methylmalonic acid were significant negative determinant of sphingomyelins, whereas phosphatidylcholine was a strong positive determinant. Conclusions: The current results support systemic alterations in phospholipids metabolism in PCa. We report on a significant decrease in plasma concentrations of sphingomyelin in elderly patients with PCa and in users of statins. The PCa-associated low sphingomyelin showed a synergy with the effect of statins. The presence of PCa was not associated with significant changes in plasma concentrations of choline or methyl metabolites. However, changes in choline absorption and tissue uptake cannot be ruled out in this study.
    No preview · Article · Jan 2016 · Biochimie
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    ABSTRACT: Purpose: Positive surgical margins (PSM) during robot-assisted radical prostatectomy (RARP) negatively influence patients' prognosis. The aim of our study was to identify risk factors for PSM in patients with organ-confined prostate cancer (PCa). Methods: A clinical database of all patients that underwent a RARP at our institution was used. Uni- and multivariable logistic regression analyses were conducted on the PSM rates for all patients with organ-confined PCa. Results: Altogether, 1,600 patients were identified, including 1,085 organ-confined PCa with a PSM rate of 7.8%. On multivariable analysis, bilateral nerve-sparing (OR 3.025, 95% CI 1.587-5.765), surgeon volume <200 cases (OR 1.881, 95% CI 1.120-3.159) and a preoperative PSA >10 ng/ml (OR 3.674, 95% CI 1.379-9.796) remained independent prognostic factors. In a subgroup of patients undergoing a nerve-sparing RARP, the quality of the prostate biopsy (OR 2.398, 95% CI 1.325-4.341) was the sole independent risk factor for a PSM. Conclusion: An elevated preoperative PSA, surgical experience and a nerve-sparing procedure are all significantly associated with a higher risk for a PSM after RARP. For those undergoing a nerve sparing RARP, an accurate preoperative biopsy with detailed information on the location of positive cores is essential to prevent PSMs.
    No preview · Article · Nov 2015 · Urologia Internationalis
  • Carsten-Henning Ohlmann · Michael Stöckle

    No preview · Article · Aug 2015 · European Urology
  • M. Saar · C. Ohlmann

    No preview · Article · Aug 2015 · TumorDiagnostik & Therapie
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    ABSTRACT: To assess clinical outcomes and reimbursement costs of open and robotic-assisted radical prostatectomies in Germany. Perioperative data of 499 open (2003-2006) and 932 (2008-2010) robotic-assisted radical prostatectomies as well as longitudinal reimbursement costs of an anonymized health insurance research database from Germany containing data of patients who underwent robotic-assisted or open radical prostatectomy were retrospectively analysed in a single-centre study. Significantly better outcomes after robotic-assisted vs. open prostatectomy were observed in regards to positive surgical margins (13.3 vs. 22.4%; p < 0.0001), intraoperative transfusions (0.1 vs. 2.6%; p < 0.0001), hospitalization (8.7 vs. 15.2 days; p < 0.0001) and duration of catheter (6.6 vs. 12.8 days; p < 0.0001). Operating time was significantly longer with robotic-assisted radical prostatectomy when compared to open surgery (184.4 vs. 128.0 min; p < 0.0001), while intraoperative complications showed a similar occurrence between both groups. Significant fewer postoperative complications were observed after robotic-assisted radical prostatectomy (26.5 vs. 42.5%; p < 0.0001) and rate of re-admission was lower for the robotic patients (13.6 vs. 19.4%; p = 0.0050). While insurance costs were higher in the 2 years before radical prostatectomy for the patients who underwent a robotic procedure (4,241.60 vs. 3,410.23 €; p = 0.202), additive costs of care of the year of surgery plus the 2 following years were less for the robotic cohort when compared to the costs incurred by the open group (21,673.71 vs. 24,512.37 €; p = 0.1676). The observed clinical advantages of robotic-assisted radical prostatectomy seem to result in reduced health insurance cost postoperatively when compared to open surgery. This should be taken into consideration regarding reimbursement and implementation of a clinically superior method. © 2015 S. Karger AG, Basel.
    No preview · Article · Jul 2015 · Urologia Internationalis
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    ABSTRACT: Sclerosing epithelioid fibrosarcoma (SEF) is a rare fibrosarcoma variant with specific histomorphology and consistent translocation (EWSR1-CREB3L1/2). To date, 110 cases have been reported; only 15 originated within the abdomen. With only 2 cases reported parallel to our study and one case briefly mentioned in a previous series, primary renal SEF is exceptionally rare but might be underrecognized. We herein describe 2 cases affecting a 23-year-old woman and a 43-year-old man. Tumor size was 22 and 4.2 cm, respectively. Patient 1 developed skeletal and multiple pulmonary metastases. She died of disease 82 months later, despite aggressive multimodality therapy. Patient 2 has no evidence of recurrence or metastasis (8 months after surgery). Histologic examination showed similar appearance with monotonous bland medium-sized epithelioid cells with rounded slightly vesicular nuclei and clear cytoplasm imparting a carcinoma-like appearance set within a highly sclerotic hyaline fibrous stroma. The tumor cells were arranged in nests, single cell cords, trabeculae, or solid sheets with frequent entrapment of renal tubules and glomeruli. Immunohistochemistry showed strong expression of vimentin, bcl2, CD99, and MUC4, whereas cytokeratin and other markers were negative. Fluorescence in situ hybridization showed a translocation involving the EWSR1 gene locus in case 2. Molecular analysis in case 1 was not successful due to poor signal quality. To our knowledge, this is the second report documenting primary renal SEF. Awareness of this entity would help avoid misinterpretation as clear cell carcinoma, sclerosing perivascular epithelioid cell tumor, Xp.11 translocation carcinoma, and other more frequent neoplasms at this site. Copyright © 2015. Published by Elsevier Inc.
    Full-text · Article · May 2015 · Annals of diagnostic pathology
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    Full-text · Article · Apr 2015 · The Journal of Urology

  • No preview · Article · Nov 2014 · Transplantation
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    ABSTRACT: The anti-androgen withdrawal syndrome (AAWS) can be seen in one-third of patients after discontinuation of first-generation non-steroidal anti-androgen therapy. With the introduction of new agents for anti-androgen therapy as well as alternate mechanisms of action, new therapeutic options before and after docetaxel chemotherapy have arisen (Ohlmann et al. in World J Urol 30(4):495-503, 2012). The question regarding the occurrence of an enzalutamide withdrawal syndrome (EWS) has not been evaluated yet. In this study, we assess prostate-specific antigen (PSA) response after discontinuation of enzalutamide. In total 31 patients with metastatic castration-resistant prostate cancer (mCRPC) underwent an enzalutamide withdrawal and were evaluated. Data were gathered from 6 centres in Germany. Patients with continuous oral administration of enzalutamide with rising serum PSA levels were evaluated, starting from enzalutamide withdrawal until subsequent therapy was initiated, follow-up ended or death of the patient occurred. Statistical evaluation was performed applying one-sided binomial testing using R-statistical software, version 3.0.1. Mean withdrawal follow-up was 6.5 weeks (range 1-26.1 weeks). None of the 31 patients showed a PSA decline. Mean relative PSA rise over all patients was 73.9 % (range 0.5-440.7 %) with a median of 44.9 %. If existent, an AAWS is at least very rare for enzalutamide in patients with mCRPC after taxane-based chemotherapy and does not play a clinical role in this setting. This may be attributed to the different pharmacodynamics of enzalutamide. Longer duration of therapy or a longer withdrawal interval may reveal a rare EWS in the future.
    No preview · Article · Apr 2014 · World Journal of Urology
  • N. Dengel · W. Feldmann · S. Siemer · M. Stoeckle · C. Ohlmann

    No preview · Article · Nov 2013 · Progrès en Urologie
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    ABSTRACT: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: There is evidence from large abdominal surgeries and some open cystectomy series that multifactorial fast-track regimens shorten postoperative convalescence without any effect on morbidity and mortality. Such a regimen is of particular interest in combination with minimally invasive techniques, as early patient recovery demands for more rapid nutrition and mobilisation schemes. The present study, in a single institution, reports on the design, application and results of a fast-track protocol in patients undergoing robot-assisted laparoscopic cystectomy. There was no evidence of a higher incidence of complications with the fast-track regimen and postoperative recovery was faster. OBJECTIVES: To evaluate the feasibility and effectiveness of a multifactorial fast-track (FT) regimen on perioperative outcomes in patients undergoing robot-assisted laparoscopic cystectomy (RALC) with extracorporeal urinary diversion. To point out that morbidity and mortality of radical cystectomy have improved markedly over the last decades and RALC is an emerging technique showing further advances in postoperative recovery, thus demanding for more rapid nutrition and mobilisation schemes. PATIENTS AND METHODS: A non-randomised cohort study of 63 patients who underwent RALC at one institution between January 2007 and March 2010. In all, 31 patients underwent RALC without FT and 31 RALC with FT. One patient required conversion to open surgery and was therefore excluded from the study. The FT regimen included early nutrition and the quickest possible mobilisation, while mechanical bowel preparation before surgery, as well as preoperative fasting and nasogastric or abdominal drains after surgery, were omitted. Demographics, perioperative and complication data (according to modified Clavien system), as well as required opioid pain medication were documented prospectively and compared between RALC patients with and without FT. RESULTS: Groups were comparable for demographics, risk factors and clinical stage as well as operative parameters, e.g. mean operating room time, estimated blood loss, lymph nodes removed and postoperative haemoglobin level. In the FT group, abdominal drains were mostly omitted and nasogastric tubes were removed immediately after surgery. There were significant differences in the mobilisation within the room (17.5 vs 31.2 h), the time to a regular diet (4.0 vs 6.6 days) and a remarkably lower use of postoperative morphine equivalents (57.3 vs 92.4 mg) for patients receiving FT. There were no significant differences in the overall complication rates or major complications based on Clavien classification. The informative value of the study is limited by its single-centre, non-randomised design, a relatively small sample size and a possible learning curve bias. CONCLUSIONS: Combining RALC with FT is feasible in the perioperative treatment of these patients. Multifactorial postoperative regimens seem to quicken postoperative recovery of RALC patients without increasing their risk of postoperative complications.
    No preview · Article · Nov 2012 · BJU International
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    ABSTRACT: Die Standardtherapie des muskelinvasiven Blasenkarzinoms ist die radikale Zystektomie und eine Harnableitung. Als offen chirurgischer Eingriff ist dieser mit einer nicht unerheblichen perioperativen Morbidität vergesellschaftet. Durch eine laparoskopische Zystektomie kann diese Morbidität gesenkt werden. Es ist jedoch noch unklar, ob die onkologischen Ergebnisse vergleichbar zur offen Operation sind, da Langzeitdaten noch fehlen. Wichtige Operationsschritte wie eine ausgedehnte Lymphadenektomie, eine Schonung des Gefäß-Nerven-Bündels bei Potenzerhalt, eine Präparation der Harnröhre bei orthotoper Neoblase und eine intrakorporale Konstruktion der Harnableitung sind bei einem robotisch assistierten Eingriff deutlich besser umsetzbar als bei der konventionellen Laparoskopie. Zudem ist die Lernkurve für die robotisch assistierte Zystektomie sehr viel steiler. Daher sollte die Zystektomie – wenn laparoskopisch – dann robotisch assistiert erfolgen.
    No preview · Article · May 2012 · Der Urologe
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    ABSTRACT: Emerging evidence suggest that microRNAs could serve as non-invasive biomarker for cancer patients. Our study was designed to analyze circulating serum microRNAs in patients with renal cell carcinoma (RCC). Serum RNA was isolated from patients with clear cell RCC (ccRCC) and non-malignant disease; an artificial microRNA (cel-miR-39) was spiked-in prior the isolation procedure to control isolation efficiency. The levels of miR-26a-2*, miR-191, miR-337-3p and miR-378 in serum were determined using quantitative real-time PCR; the microRNA levels were normalized to cel-miR-39. First, miR-26a-2*, miR-191, miR-337-3p and miR-378 were quantified in serum of each 25 patients with ccRCC and non-malignant disease. The level of miR-378 was significantly increased in ccRCC patients, and thus chosen for validation. The analysis of miR-378 in the validation cohort with 117 RCC patients and 123 control subjects did not confirm a different level of miR-378. Also, miR-378 was not correlated to pT-stage, lymph node/distant metastasis, vascular invasion and Fuhrman grade. The analysis of circulating serum levels of miR-26a-2*, miR-191, miR-337-3p and miR-378 is unlikely to provide helpful diagnostic/prognostic information in RCC patients.
    No preview · Article · Apr 2012
  • J Kamradt · M Saar · C Ohlmann · S Siemer · M Stöckle
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    ABSTRACT: The standard therapy for muscle invasive bladder cancer is radical cystectomy and urinary diversion. For open surgery this procedure has notable perioperative morbidity. Performing laparoscopic cystectomy can reduce this morbidity. So far it remains unclear, whether the oncologic outcome of the laparoscopic approach is comparable to open surgery or not due to a lack of long-term follow-up data. Important surgical steps, such as extended lymphadenectomy, sparing of the neurovascular bundle for preservation of potency, preparation of the urethra for orthotopic neobladder and intracorporeal construction of a urinary diversion can be achieved much more easily with a robot-assisted approach than with conventional laparoscopy. Furthermore, the learning curve for robot-assisted cystectomy is much steeper. Therefore, if a laparoscopic cystectomy is performed, it should be performed using a robot-assisted approach.
    No preview · Article · Apr 2012 · Der Urologe

  • No preview · Article · Feb 2012 · European Urology Supplements

  • No preview · Article · Feb 2012 · European Urology Supplements
  • Z. Bütow · C. Ohlmann · J. Kamradt · S. Siemer · M. Stöckle

    No preview · Article · Sep 2011 · Urology
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    Robin Epplen · Michael Stöckle · Udo Engelmann · Axel Heidenreich · Carsten-Henning Ohlmann
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    ABSTRACT: Ibandronate, one of the most potent bisphosphonates, has been shown to inhibit growth of various cancer cell lines. In contrast, little is known about the effects of ibandronate on prostate cancer cells. Therefore the aim of our study was to characterize the effects of ibandronate alone and in combination with docetaxel on the growth of prostate cancer cell lines and to identify the underlying signalling pathways. Material and methods. The prostate cancer cell lines LNCaP and PC-3 were treated with increasing concentrations of ibandronate and docetaxel alone and in combination. Viable cell number was measured after five days using a hemocytometer and the MTT-method. The effects of ibandronate were tentatively antagonized by addition of farnesyl-pyrophosphate (FPP) or farnesol (FOH). Results. Ibandronate inhibits growth of both prostate cancer cell lines in a dose dependent manner. In combination with docetaxel, synergistic effects are found as evidenced by a combination index (CI) of <1. Addition of FOH and FPP completely antagonized the growth inhibitory effects of ibandronate on both cell lines. Surprisingly, in combination with ibandronate and docetaxel, FOH further increased growth inhibition instead of antagonizing the growth inhibitory effects of ibandronate. Furthermore, FOH alone appeared to be a potent inhibitor of tumor cell growth. Discussion. Ibandronate effectively inhibits growth of prostate cancer cell lines via inhibition of the farnesyl-IPP-synthase and exhibits synergistic effects with docetaxel. In addition, FOH is a potent inhibitor of prostate cancer cell lines and may display an interesting treatment option for patients with CRPC.
    Preview · Article · Jan 2011 · Acta oncologica (Stockholm, Sweden)
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    ABSTRACT: In order to improve the efficacy of targeted therapy trials, the expression profiles of several molecular markers that are potential candidates for targeted therapy were analyzed in patients with progressive castration-resistant prostate cancer. Paraffin-embedded samples of tumor tissue from 51 patients obtained from biopsies of metastases or remaining prostates were analyzed immunohistochemically for the expression of EGFR, PDGFRβ, Her-2/neu, c-Kit, and VEGF. Staining was analyzed according to the percentage of positively stained tumor cells and the intensity of staining. According to the different cut-off values of 10%, 30%, 50%, or 70% for the percentage of positively stained cells, different rates of expression were found. Expression rates ranged from 30.6% to 61.2% for EGFR, from 34.7% to 57.1% for PDGFRβ, from 9.6% to 28.8% for Her-2/neu, from 12.5% to 22.4% for c-Kit, and from 51.1% to 74.5% for VEGF. Defining positive expression as ≥ 30% positively stained tumor cells, with an intensity of staining of ≥ 2+, resulted in positive expression of EGFR in 38.8%, PDGFRβ in 24.5%, Her-2/neu in 13.5%, c-Kit in 6.4%, and VEGF in 44.7% of the patients. Our results demonstrate simultaneous expression of several markers in castration-resistant prostate cancer tissue. Translation of the results into modern, multi-arm clinical trial designs will improve the efficacy of recruiting and obtaining results, compared with multiple double-arm trials.
    No preview · Article · Nov 2009 · Urologic Oncology
  • Carsten-Henning Ohlmann

    No preview · Article · Feb 2009 · European Urology

Publication Stats

188 Citations
153.56 Total Impact Points

Institutions

  • 2009-2014
    • Universität des Saarlandes
      • Klinik für Urologie und Kinderurologie
      Saarbrücken, Saarland, Germany
  • 2012
    • Universitätsklinikum des Saarlandes
      Homburg, Saarland, Germany
  • 2004-2011
    • University of Cologne
      • Department of Urology
      Köln, North Rhine-Westphalia, Germany
  • 2003-2006
    • Philipps-Universität Marburg
      • Klinik für Urologie und Kinderurologie (Marburg)
      Marburg, Hesse, Germany