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Featured researches published by Oliver Gross.


The Journal of Urology | 2009

Lithium Triborate Laser Vaporization of the Prostate Using the 120 W, High Performance System Laser: High Performance All the Way?

Thomas Hermanns; Daniel D. Strebel; Lukas J. Hefermehl; Oliver Gross; Ashkan Mortezavi; Alexander Müller; Daniel Eberli; Michael Müntener; Maurice Stephan Michel; Alexander H. Meier; Tullio Sulser; Hans-Helge Seifert

PURPOSE Technical modifications of the 120 W lithium-triborate laser have been implemented to increase power output, and prevent laser fiber degradation and loss of power output during laser vaporization of the prostate. However, visible alterations at the fiber tip and the subjective impression of decreasing ablative effectiveness during lithium-triborate laser vaporization indicate that delivering constantly high laser power remains a relevant problem. Thus, we evaluated the extent of laser fiber degradation and loss of power output during 120 W lithium-triborate laser vaporization of the prostate. MATERIALS AND METHODS We investigated 46 laser fibers during routine 120 W lithium-triborate laser vaporization in 35 patients with prostatic bladder outflow obstruction. Laser beam power was measured at baseline and after the application of each 25 kJ during laser vaporization. Fiber tips were microscopically examined after the procedure. RESULTS Mild to moderate degradation at the emission window occurred in all fibers, associated with a loss of power output. A steep decrease to a median power output of 57.3% of baseline was detected after applying the first 25 kJ. Median power output at the end of the defined 275 kJ lifespan of the fibers was 48.8%. CONCLUSIONS Despite technical refinements of the 120 W lithium-triborate laser fiber degradation and significantly decreased power output are still detectable during the procedure. Laser fibers are not fully appropriate for the high power delivery of the new system. There is still potential for further improvement in the laser performance.


British Journal of Cancer | 2018

Systemic inflammatory markers have independent prognostic value in patients with metastatic testicular germ cell tumours undergoing first-line chemotherapy

Christian Fankhauser; Sophia Sander; Lisa Roth; Oliver Gross; Daniel Eberli; Tullio Sulser; Burkhardt Seifert; Joerg Beyer; Thomas Hermanns

Background:The prognostic utility of systemic inflammatory markers has so far not been investigated in patients with metastatic testicular germ cell tumours (GCTs).Methods:International Germ Cell Cancer Cooperative Group (IGCCCG) risk groups and blood-based systemic inflammatory markers (haemoglobin, leukocytes, platelets (P), neutrophils (N), lymphocytes (L), C-reactive protein (CRP) and albumin) of 146 patients undergoing first-line chemotherapy for GCT were retrieved. In addition, N to L ratio (NLR), P to L ratio and the systemic immune-inflammation index (SII=N × P/L) were calculated. The prognostic ability of these markers for overall survival (OS) were assessed using regression analyses and Kaplan–Meier curves with log-rank tests.Results:In univariate Cox regression, low haemoglobin and albumin as well as high leukocytes, N, NLR, SII and CRP were associated with a shorter OS. In multivariable Cox regression analyses, high leukocyte (hazard ratio (HR) 1.274 (95% confidence interval (CI) 1.057–1.535); P=0.011) and N count (1.470 (1.092–1.980); P=0.011), higher NLR (84.5 (2.2–3193.4); P=0.017) and SII (12.15 (1.17–126.26); P=0.037) remained independent prognostic predictors for OS besides the IGCCCG risk groups.Conclusions:Systemic inflammatory markers might have prognostic utility for patients with metastatic GCT. The planned IGCCCG update could be an opportunity to test these markers in a larger data set.


Journal of Endourology | 2013

Pure bipolar plasma vaporization of the prostate: the Zürich experience.

Benedikt Kranzbühler; Marian S. Wettstein; Christian Fankhauser; Nico C. Grossmann; Oliver Gross; Cédric Poyet; Boris Fischer; Matthias Zimmermann; Tullio Sulser; Alexander Müller; Thomas Hermanns

INTRODUCTION AND OBJECTIVES Bipolar plasma vaporization (BPV) has been introduced as an alternative to transurethral resection of the prostate (TURP). Promising short-term results, but inferior mid-term results compared to TURP have been reported following first-generation bipolar electrovaporization. Outcome data following second-generation BPV are still scarce. The aim of this investigation was to evaluate the intra- and postoperative outcomes of contemporary BPV in a center with long-standing expertise on laser vaporization of the prostate. METHODS A consecutive series of 83 patients undergoing BPV in a tertiary referral center was prospectively evaluated. The investigated outcome parameters included the maximum flow rate (Qmax), postvoid residual volume, International Prostate Symptom Score (IPSS)/quality of life (Qol), and prostate-specific antigen (PSA) tests. Follow-up investigations took place after 6 weeks, 6 months, and 12 months. The Wilcoxon signed-rank test was used to compare pre- and post-treatment parameters. RESULTS The median (range) preoperative prostate volume was 41 mL (17-111 mL). The preoperative IPSS, Qol, Qmax, and residual volume were 16 (2-35), 4 (0-6), 10.1 mL/s (3-29.3 mL/s), and 87 mL (0-1000 mL), respectively. One third of the patients were undergoing platelet aggregation inhibition (PAI). No intraoperative complications occurred. Postoperatively, 13 patients (15.7%) had to be recatheterized. Three patients (3.6%) had clot retention and 28 patients (34%) reported any grade of dysuria. After 6 weeks, all outcome parameters improved significantly and remained improved over the 12-month observation period [IPSS: 3 (0-2); Qol: 1 (0-4); Qmax: 17.2 mL/s (3.2-56 mL/s); residual volume 11 mL (0-190 mL)]. The PSA reduction was 60% at study conclusion. Three patients (3.6%) developed a urethral stricture and four patients (4.8%) bladder neck sclerosis. Re-resections were not necessary. CONCLUSIONS Contemporary BPV is a safe and efficacious treatment option even for patients undergoing PAI. Early urinary retention and temporary dysuria seem to be specific side effects of the treatment. Bleeding complications are rare. Long-term follow-up is needed to confirm these promising short-term results.


The Journal of Urology | 2018

Diagnostic accuracy of mpMRI and fusion-guided targeted biopsy evaluated by transperineal template saturation prostate biopsy for the detection and characterization of prostate cancer

Ashkan Mortezavi; Olivia Märzendorfer; Olivio F. Donati; Gianluca Rizzi; Niels J. Rupp; Marian S. Wettstein; Oliver Gross; Tullio Sulser; Thomas Hermanns; Daniel Eberli

Purpose: We evaluated the diagnostic accuracy of multiparametric magnetic resonance imaging and multiparametric magnetic resonance imaging/transrectal ultrasound fusion guided targeted biopsy against that of transperineal template saturation prostate biopsy to detect prostate cancer. Materials and Methods: We retrospectively analyzed the records of 415 men who consecutively presented for prostate biopsy between November 2014 and September 2016 at our tertiary care center. Multiparametric magnetic resonance imaging was performed using a 3 Tesla device without an endorectal coil, followed by transperineal template saturation prostate biopsy with the BiopSee® fusion system. Additional fusion guided targeted biopsy was done in men with a suspicious lesion on multiparametric magnetic resonance imaging, defined as Likert score 3 to 5. Any Gleason pattern 4 or greater was defined as clinically significant prostate cancer. The detection rates of multiparametric magnetic resonance imaging and fusion guided targeted biopsy were compared with the detection rate of transperineal template saturation prostate biopsy using the McNemar test. Results: We obtained a median of 40 (range 30 to 55) and 3 (range 2 to 4) transperineal template saturation prostate biopsy and fusion guided targeted biopsy cores, respectively. Of the 124 patients (29.9%) without a suspicious lesion on multiparametric magnetic resonance imaging 32 (25.8%) were found to have clinically significant prostate cancer on transperineal template saturation prostate biopsy. Of the 291 patients (70.1%) with a Likert score of 3 to 5 clinically significant prostate cancer was detected in 129 (44.3%) by multiparametric magnetic resonance imaging fusion guided targeted biopsy, in 176 (60.5%) by transperineal template saturation prostate biopsy and in 187 (64.3%) by the combined approach. Overall 58 cases (19.9%) of clinically significant prostate cancer would have been missed if fusion guided targeted biopsy had been performed exclusively. The sensitivity of multiparametric magnetic resonance imaging and fusion guided targeted biopsy for clinically significant prostate cancer was 84.6% and 56.7% with a negative likelihood ratio of 0.35 and 0.46, respectively. Conclusions: Multiparametric magnetic resonance imaging alone should not be performed as a triage test due to a substantial number of false‐negative cases with clinically significant prostate cancer. Systematic biopsy outperformed fusion guided targeted biopsy. Therefore, it will remain crucial in the diagnostic pathway of prostate cancer.


Praxis Journal of Philosophy | 2015

Erektions- und Ejakulationsstörungen

Oliver Gross; Tullio Sulser; Daniel Eberli

The inability to achieve an erection of the penis sufficient for sexual activity is called erectile dysfunction (ED). In most cases, the diagnosis can be made by medical history. The prevalence of ED in men at the age of 65 has been reported to be up to 50%. Premature ejaculation has a prevalence, up to 20% and is the most frequent ejaculatory dysfunction. The etiology of ED can involve psychological, vascular, neurogenic, hormonal or urogenital pathologies. The main pathophysiological mechanisms of ED are vascular disorders such as diabetes mellitus and atherosclerosis. Because of the common pathophysiology, patients diagnosed with ED should have a diagnostic work-up for systemic vascular pathologies to prevent concomitant cardiac events. Treatment options include invasive and non-invasive procedures.


World Journal of Urology | 2018

Inhibition of autophagy significantly increases the antitumor effect of Abiraterone in prostate cancer

Ashkan Mortezavi; Souzan Salemi; Benedikt Kranzbühler; Oliver Gross; Tullio Sulser; Hans-Uwe Simon; Daniel Eberli

PurposeAbiraterone acetate (AA) plus prednisone is an approved treatment of advanced prostate cancer (PCa). Autophagy is linked to drug resistance in numerous types of cancers. We hypothesized, that upregulation of autophagy is one of the mechanisms by which PCa cells survive AA anti-tumor treatment and therefore evaluated the potential effect of a combination with autophagy inhibition.MethodsHuman PCa LNCaP cell lines were cultured in steroid-free medium and treated with AA. Autophagy was inhibited by 3-methyladenine, chloroquine and ATG5 siRNA knock-down. Cell viability and apoptosis was assessed by flow cytometry and fluorescence microscopy, and autophagy was monitored by immunohistochemistry, AUTOdot and Western blotting.ResultsWestern blot revealed upregulation of ATG5 and LC3 II with a reduction of p62 protein expression in AA-treated cells, indicating upregulation of autophagy. These data were supported by results obtained with immunocytochemistry and AUTOdot assays. Using flow cytometry, we showed that combining AA with autophagy inhibition significantly impaired cell viability (1.3–1.6-fold, p < 0.001) and increased apoptosis (1.4–1.5-fold, p < 0.001) compared to AA treatment alone.ConclusionsAA activates autophagy as a cytoprotective mechanism in LNCaP prostate cancer cells and targeting of autophagy enhances the antitumor effect of the compound.


The Journal of Urology | 2017

MP38-10 COMPLICATIONS FOLLOWING EXTENDED TRANSPERINEAL TEMPLATE MAPPING MRI/TRUS FUSION BIOPSY OF THE PROSTATE – INITIAL EXPERIENCE FROM 421 PROCEDURES

Oliver Gross; Basil Kaufmann; Ashkan Mortezavi; Olivia Maerzendorfer; Marian S. Wettstein; Tullio Sulser; Daniel Eberli

INTRODUCTION AND OBJECTIVES: Transperineal template mapping MRI/TRUS fusion biopsy (TMBx) offers superior accuracy and allows optimal risk stratification for patients detected with prostate cancer. However, limited data is available regarding complications and morbidity following TMBx. The goal of this retrospective analysis was to obtain the complication rate follwing TMBx in a large series. METHODS: The records of 402 consecutive patients undergoing TMBx between June 2013 and August 2016 were reviewed. All patients received a single shot antibiotic prophylaxis with 80 mg gentamicin. All underwent transperineal fusion targeted biopsy of MRIsuspicious lesions (median 3 cores per lesion) and transperineal extended template biopsy (median 41 cores). The complications were reported according to the modified Clavien-Dindo classification system. RESULTS: Of the 421 biopsies, 371 (88.1%) had an uneventful biopsywithout complications. Twenty patients (4.8%) showedpost-biopsy complications requiring an outpatient consultation or hospital admission within 30 days of the procedure. According to the Clavien-Dindo classification there were 25 patients (5.9%) with grade I complications, 24 (5.7%) with grade II and one patient (0.2%) with a grade IIIb complication (TUR-P within 30 days as a patients desire). Eleven patients (2.6%) developed an urosepsis (fever >38.5 C), 38 (9%) had an urinary retention requiring urethral catheterization and two (0.5%) had an acute bacterial prostatitis. Of the eleven patients with urosepsis, seven carried Escherichia coli, the other four cases were ESBL, Enterococcus faecalis, Serratia marcenscens and Enterobacter cloacae complex with Staphyloccocus aureus. Those patients had to be hospitalised for 2.5 days on average (range 1-7 days). 37 patients (8.8%) mentioned haematospermia while 93 (22.1%) noticed haematuria within 30 days of the procedure. A binomial logistic regressionshowed that an increasedprostate volumewasassociatedwith an increased likelihood of exhibiting urinary retention (p 1⁄4 0.006). CONCLUSIONS: In this analysis we demonstrated a low morbidity following TMBx. The procedure is very well tolerated and safe for patients. Especially the rate of major infections and urosepsis are low. Haematuria and haematospermia were very common but selflimiting in most of the cases. However, urinary retention is a major complication with 9% of all cases and is associated with increased prostate volume. Therefore we now leave the catheter for two days in patients with larger prostate glands.


The Journal of Urology | 2017

MP02-02 PURE BIPOLAR PLASMA VAPORIZATION OF THE PROSTATE: 5-YEAR FOLLOW-UP FROM A PROSPECTIVE 3D ULTRASOUND VOLUMETRY STUDY

Benedikt Kranzbühler; Oliver Gross; Christian Fankhauser; Marian S. Wettstein; Nico C. Grossmann; Etienne Xavier Keller; Daniel Eberli; Tullio Sulser; Cédric Poyet; Thomas Hermanns

INTRODUCTION AND OBJECTIVES: Pure bipolar plasma vaporization (BPV) has been established as low-morbidity alternative to conventional transurethral resection of the prostate (TURP). Low intraand postoperative morbidity as well as excellent functional short-term results have been reported. However, long-term outcome is still lacking. The extent of prostate tissue removal, which impacts the durability of postoperative functional improvements, is also unknown after BPV. The aim of the present study was to investigate the long-term functional outcome and associated prostate volume changes following pure BPV of the prostate. METHODS: A consecutive series of 75 patients treated by pure BPV in a tertiary care academic center was prospectively investigated. Prostate volume was assessed using planimetric volumetry following transrectal 3D-ultrasound of the prostate. Prostate volume and clinical parameters were recorded preoperatively and regularly after BPV (after catheter removal, 6W, 6M, 1, 3 and 5Y). RESULTS: Median (interquartile range; IQR) preoperative prostate volume was 41 ml (26.8ml), IPSS 16 (10), QoL 4 (2), Qmax 10.1ml/s (8ml/s), PVR 91ml (140ml) and PSA 2.57ng/ml (3.5ng/ml). A significant relative prostate volume reduction (RVR) of 33.3% (IQR: 22.3%; p<0.001) was already detectable at the time of catheter removal. Relative volume reduction increased significantly up to 12M (6W: 45.9% (17.4%; p<0.001), 6M: 50.5% (16.1%; p<0.001) and 12M 52.2% (17.4%; p1⁄40.014). After 12M the RVR remained stable with 50.6% (14.3%; p1⁄40.58) after 3Y and 52.6% (14.1%; p1⁄40.59) after 5Y. Postoperatively, all investigated clinical parameters improved significantly and remained stable during the 5Y follow-up [5Y results (IQR): IPSS: 3 (8), QoL: 1 (1), Qmax: 16.3ml/s (13.7ml/s), PVR 20ml (46.5ml)]. Median PSA reduction after 5Y was 55% (36.2%). During the observation period 9 urethral strictures (12%) were detected of which 7 were de novo strictures. Bladder neck incisions for postoperative bladder neck stenosis were performed in 6 patients (8%). Median prostate volume in these patients was 30.6ml (18.2ml). Re-resections for regrown adenoma were not necessary. CONCLUSIONS: Low intraand postoperative morbidity in combination with excellent functional outcome and durable prostate volume reduction confirm the role of contemporary BPV as a minimally invasive alternative to conventional TURP. However, postoperative bladder neck stenoses appeared rather frequent after BPV and might be a procedure-specific drawback.


The Journal of Urology | 2016

MP16-13 MINIMIZING THE GLEASON SCORE UPGRADE FROM BIOPSY TO PROSTATECTOMY SPECIMEN THROUGH MPMRI AND TEMPLATE MAPPING FUSION BIOPSY

Oliver Gross; Ashkan Mortezavi; Lilian Neuhaus; Tullio Sulser; Daniel Eberli

INTRODUCTION AND OBJECTIVES: Precise risk stratification is essential in times where alternative treatment options to radical prostatectomy (RP) such as active surveillance, brachytherapy, radiotherapy and focal treatment of prostate cancer (PC) are available. However, the current concordance of conventional transrectal prostate biopsy (PB) regarding Gleason score (GS) is low 53-69%, when compared to RP specimens. Multiparametric MRI (mpMRI) of the prostate and fusion transperineal prostate mapping (TPM) biopsy might allow increasing the concordance facilitate the decision making. METHODS: A total of 348 patients were included in this retrospective analysis. Pathological reports were analyzed from patients who underwent radical prostatectomy (RP) and compared to GS acquired by PB or TPM after mpMRI. MpMRI fusion TPM was performed by taking biopsy cores from 20 predefined regions of the prostate and from MRI suspicious lesions after fusion. RESULTS: Patients with PB before RP demonstrated an overall increase in GS of 30% and a significant increase of 2 GS steps was detectable in 15%. Patients with a mpMRI and TPM demonstrated an increase in GS only 16.6% with maximally one GS step. This difference is even more pronounced if GS 3+4 and 4+3 are not differentiated and summarized to GS 7 only. In this case the GS upgrade is 6.3% for TPM compared to 22.8% for PB. However, the amount of downgraded GS after RP is higher for TPM (TPM 31.2% vs. PB 14.0%). The detailed analysis of the TPM group showed that GS upgrades were limited to GS 6 and 7a. None of the >7b GS demonstrated a GS upgrade indicating the superior precision of the extended TPM. CONCLUSIONS: MpMRI with TPM allows for a more precise risk stratification by displaying the true GS more often. Optimal diagnosis with minimal risk of underestimating the disease burden is crucial to select patients for focal treatment and to prevent over-treatment by radical therapy options. This novel diagnostic strategy will help counselling patients before any treatment strategy.


Proceedings of SPIE | 2012

Tissue ablation after 120W greenlight laser vaporization and bipolar plasma vaporization of the prostate. A comparison using transrectal three-dimensional ultrasound volumetry

Benedikt Kranzbühler; Oliver Gross; Christian Fankhauser; Lukas J. Hefermehl; Cédric Poyet; Michael Müntener; Hans-Helge Seifert; Matthias Zimmermann; Tullio Sulser; Alexander Müller; Thomas Hermanns

Introduction and objectives: Greenlight laser vaporization (LV) of the prostate is characterized by simultaneous vaporization and coagulation of prostatic tissue resulting in tissue ablation together with excellent hemostasis during the procedure. It has been reported that bipolar plasma vaporization (BPV) of the prostate might be an alternative for LV. So far, it has not been shown that BPV is as effective as LV in terms of tissue ablation or hemostasis. We performed transrectal three-dimensional ultrasound investigations to compare the efficiency of tissue ablation between LV and BPV. Methods: Between 11.2009 and 5.2011, 50 patients underwent pure BPV in our institution. These patients were matched with regard to the pre-operative prostate volume to 50 LV patients from our existing 3D-volumetry-database. Transrectal 3D ultrasound and planimetric volumetry of the prostate were performed pre-operatively, after catheter removal, 6 weeks and 6 months. Results: Median pre-operative prostate volume was not significantly different between the two groups (45.3ml vs. 45.4ml; p=1.0). After catheter removal, median absolute volume reduction (BPV 12.4ml, LV 6.55ml) as well as relative volume reduction (27.8% vs. 16.4%) were significantly higher in the BPV group (p<0.001). After six weeks (42.9% vs. 33.3%) and six months (47.2% vs. 39.7%), relative volume reduction remained significantly higher in the BPV group (p<0.001). Absolute volume reduction was non-significantly higher in the BPV group after six weeks (18.4ml, 13.8ml; p=0.051) and six months (20.8ml, 18ml; p=0.3). Clinical outcome parameters improved significantly in both groups without relevant differences between the groups. Conclusions: Both vaporization techniques result in efficient tissue ablation with initial prostatic swelling. BPV seems to be superior due to a higher relative volume reduction. This difference had no clinical impact after a follow-up of 6M.

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