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Featured researches published by Alexandre R. Zlotta.


European Urology | 2010

An Updated Critical Analysis of the Treatment Strategy for Newly Diagnosed High-grade T1 (Previously T1G3) Bladder Cancer

Girish Kulkarni; Oliver W. Hakenberg; J.E. Gschwend; George N. Thalmann; Wassim Kassouf; Ashish M. Kamat; Alexandre R. Zlotta

CONTEXTnHigh-grade T1 (formerly T1G3) bladder cancer (BCa) has a high propensity to recur and progress. As a result, decisions pertaining to its treatment are difficult. Treatment with bacillus Calmette-Guérin (BCG) risks progression and metastases but may preserve the bladder. Cystectomy may offer the best opportunity for cure but is associated with morbidity and a risk of mortality, and it may constitute potential overtreatment for many cases of T1G3 tumours. For purposes of this review, we continue to refer to high-grade T1 lesions as T1G3.nnnOBJECTIVEnTo review the current literature on the management of T1G3 BCa and to provide recommendations for its treatment.nnnEVIDENCE ACQUISITIONnA National Center for Biotechnology Information (NCBI) PubMed search for relevant articles published between 1996 and 9 January 2009 was performed using the Medical Subject Headings T1G3 or T1 and Bladder cancer. Articles relevant to the treatment of T1G3 BCa were retained.nnnEVIDENCE SYNTHESISnThe diagnosis of T1G3 disease is difficult because pathologic staging is often unreliable and because of the risk of significant understaging at initial transurethral resection (TUR) of bladder tumour. A secondary restaging TUR is recommended for all cases of T1G3. A single dose of immediate post-TUR chemotherapy is recommended. For a bladder-sparing approach, intravesical BCG should be given as induction with maintenance dosing. Immediate or early radical cystectomy (RC) should be offered to all patients with recurrent or multifocal T1G3 disease, those who are at high risk of progression, and those failing BCG treatment.nnnCONCLUSIONSnBoth bladder preservation and RC are appropriate options for T1G3 BCa. Risk stratification of patients based on pathologic features at initial TUR or at recurrence can select those most appropriate for bladder preservation compared to those for whom cystectomy should be strongly considered.


The Journal of Urology | 2009

THE FGFR3 MUTATION IS RELATED TO FAVORABLE PT1 BLADDER CANCER

Bas W.G. van Rhijn; Theo H. van der Kwast; Liyang Liu; Neil Fleshner; Peter J. Boström; André N. Vis; Sultan Alkhateeb; Chris H. Bangma; Michael A.S. Jewett; Ellen C. Zwarthoff; Alexandre R. Zlotta; Bharati Bapat

PURPOSEnStage pT1 bladder cancer comprises a heterogeneous group of tumors for which different management options are advocated. FGFR3 mutations are linked to favorable (low grade/stage) pTa bladder cancer while altered P53 is common in cases of high grade, muscle invasive (pT2 or greater) bladder cancer. We determined the frequency of FGFR3 mutations and P53 alterations in patients with pT1 bladder cancer and correlated these data to histopathological variables and clinical outcomes.nnnMATERIALS AND METHODSnWe included 132 patients with primary pT1 bladder cancer from a total of 2 academic centers. A uropathologist reviewed the slides for grade and confirmed the pT1 diagnosis. FGFR3 mutation status was examined by SNaPshot® analysis and P53 expression was determined by standard immunohistochemistry. Kaplan-Meier and multivariate analyses were used to assess progression.nnnRESULTSnFGFR3 mutations were detected in 37 of 132 pT1 bladder cancer cases (28%) and altered P53 was seen in 71 (54%). Only 8% of patients had the 2 molecular alterations (p = 0.001). FGFR3 mutation correlated with lower grade and altered P53 correlated with high grade pT1 bladder cancer. Median followup was 6.5 years. FGFR3 mutation status and carcinoma in situ were significant for predicting progression on univariate and multivariate analyses but P53 status was not.nnnCONCLUSIONSnFGFR3 mutations selectively identify patients with pT1 bladder cancer who have favorable disease characteristics. Further study may confirm that FGFR3 identifies those who would benefit from a conservative approach to the disease.


Molecular Carcinogenesis | 2016

Sonic hedgehog (Shh) signaling promotes tumorigenicity and stemness via activation of epithelial-to-mesenchymal transition (EMT) in bladder cancer

Syed S. Islam; Reza Bayat Mokhtari; A.S. Noman; M. Uddin; M.Z. Rahman; M.A. Azadi; Alexandre R. Zlotta; T.H. Van Der Kwast; Herman Yeger; Walid A. Farhat

Activation of the sonic hedgehog (Shh) signaling pathway controls tumorigenesis in a variety of cancers. Here, we show a role for Shh signaling in the promotion of epithelial‐to‐mesenchymal transition (EMT), tumorigenicity, and stemness in the bladder cancer. EMT induction was assessed by the decreased expression of E‐cadherin and ZO‐1 and increased expression of N‐cadherin. The induced EMT was associated with increased cell motility, invasiveness, and clonogenicity. These progression relevant behaviors were attenuated by treatment with Hh inhibitors cyclopamine and GDC‐0449, and after knockdown by Shh‐siRNA, and led to reversal of the EMT phenotype. The results with HTB‐9 were confirmed using a second bladder cancer cell line, BFTC905 (DM). In a xenograft mouse model TGF‐β1 treated HTB‐9 cells exhibited enhanced tumor growth. Although normal bladder epithelial cells could also undergo EMT and upregulate Shh with TGF‐β1 they did not exhibit tumorigenicity. The TGF‐β1 treated HTB‐9 xenografts showed strong evidence for a switch to a more stem cell like phenotype, with functional activation of CD133, Sox2, Nanog, and Oct4. The bladder cancer specific stem cell markers CK5 and CK14 were upregulated in the TGF‐β1 treated xenograft tumor samples, while CD44 remained unchanged in both treated and untreated tumors. Immunohistochemical analysis of 22 primary human bladder tumors indicated that Shh expression was positively correlated with tumor grade and stage. Elevated expression of Ki‐67, Shh, Gli2, and N‐cadherin were observed in the high grade and stage human bladder tumor samples, and conversely, the downregulation of these genes were observed in the low grade and stage tumor samples. Collectively, this study indicates that TGF‐β1‐induced Shh may regulate EMT and tumorigenicity in bladder cancer. Our studies reveal that the TGF‐β1 induction of EMT and Shh is cell type context dependent. Thus, targeting the Shh pathway could be clinically beneficial in the ability to reverse the EMT phenotype of tumor cells and potentially inhibit bladder cancer progression and metastasis.


BJUI | 2009

Pathological stage review is indicated in primary pT1 bladder cancer

Bas W.G. van Rhijn; Theo H. van der Kwast; David Kakiashvili; Neil Fleshner; Madelon N.M. van der Aa; Sultan Alkhateeb; Chris H. Bangma; Michael A.S. Jewett; Alexandre R. Zlotta

Study Type – Diagnosis (case series)u2028Level of Evidenceu20034


European Urology | 2014

Prevalence of Inflammation and Benign Prostatic Hyperplasia on Autopsy in Asian and Caucasian Men

Alexandre R. Zlotta; Shin Egawa; Dmitry Pushkar; Alexander Govorov; Takahiro Kimura; Masahito Kido; Hiroyuki Takahashi; C. Kuk; Marta Kovylina; Najla Aldaoud; Neil Fleshner; Antonio Finelli; Laurence Klotz; G. Lockwood; Jenna Sykes; Theodorus van der Kwast

UNLABELLEDnInflammation has been suggested to be involved in the pathogenesis of benign prostatic hyperplasia (BPH). We studied the prevalence of inflammation and BPH in Asian and Caucasian men on prostate glands (n=320) obtained during autopsy in Moscow, Russia (Caucasian men, n=220), and Tokyo, Japan (Asian men, n=100). We correlated the presence and grade of acute inflammation (AI) or chronic inflammation (CI) and BPH. AI, CI, and histologic BPH were analyzed in a blinded fashion using a grading system (0-3). We used the Cochran-Armitage test for associations between the degree of BPH and clinical variables and proportional odds logistic regression models in multivariable analysis. Histologic BPH was observed in a similar proportion of Asian and Caucasian men (p=0.94). CI was found in>70% of men in both the Asian and Caucasian groups (p>0.05). Higher BPH scores were associated with more CI (p<0.001). In multivariate analyses, individuals with CI were 6.8 times more likely to have a higher BPH score than individuals without (p<0.0001). Men included in this study presented at the hospital and their symptomatic status was not known. The prevalence of CI and BPH on autopsy is similar in Asian and Caucasian men despite very different diet and lifestyle. CI is strongly associated in both groups with BPH.nnnPATIENT SUMMARYnIn this study, we looked at the prevalence of inflammation and benign prostatic hyperplasia (BPH) on autopsy in Asian and Caucasian men. We found chronic inflammation in>70% of men on autopsy. More chronic inflammation was associated with more BPH.


European Urology | 2014

A Negative Confirmatory Biopsy Among Men on Active Surveillance for Prostate Cancer Does Not Protect Them from Histologic Grade Progression

Lih-Ming Wong; Shabbir M.H. Alibhai; Greg Trottier; Narhari Timilshina; Theodorus van der Kwast; Alexandre R. Zlotta; Nathan Lawrentschuk; Girish Kulkarni; Robert J. Hamilton; Sarah Ferrara; David Margel; J. Trachtenberg; Michael A.S. Jewett; Ants Toi; Andrew Evans; Neil Fleshner; Antonio Finelli

BACKGROUNDnMany men (21-52%) are reported to have no cancer on the second, also known as the confirmatory, biopsy (B2) for prostate cancer active surveillance (AS). If these men had a reduced risk of pathologic progression, particularly grade related, the intensity of their follow-up could be decreased.nnnOBJECTIVEnTo investigate if men with no cancer on B2 are less likely to undergo subsequent pathologic progression.nnnDESIGN, SETTING, AND PARTICIPANTSnMen were identified from our tertiary care center AS prostate cancer database (1995-2012). Eligibility criteria were prostate-specific antigen (PSA) ≤ 10, cT2 or lower, no Gleason grade 4 or 5, three or fewer positive cores, and no core >50% involved. Only patients with three or more biopsies were selected and then dichotomized on cancer status (yes or no) at B2.nnnINTERVENTION AS OUTCOME MEASUREMENTS AND STATISTICAL ANALYSISnPathologic progression was defined as grade (advancement in Gleason score) and/or volume (more than three positive cores, >50% core involved). Progression-free survival was compared. Predictors of progression were investigated using a Cox proportional hazards model.nnnRESULTS AND LIMITATIONSnOf the 286 patients remaining on AS after B2, 149 (52%) had no cancer and 137 (48%) had cancer. The median follow-up after B2 was 41 mo (interquartile range [IQR]: 26.5-61.9). Progression-free survival at 5 yr was 85.2% versus 67.3% for negative B2 versus cancer on B2, respectively (p = 0.002). Men with no cancer at B2 had a 53% reduction in risk of subsequent progression (hazard ratio [HR]: 0.47; 95% confidence interval [CI], 0.29-0.77; p = 0.003). Subanalysis showed prognostic indicators of volume-related progression were absence of cancer (HR: 0.36; 95% CI, 0.20-0.62; p = 0.0006) and PSA density (HR: 1.79; 95% CI, 1.12-2.89; p = 0.01). The only predictor of grade-related progression was age (HR: 1.05; 95% CI, 1.00-1.10; p = 0.04). Retrospective analysis was the major limitation of the study.nnnCONCLUSIONSnAbsence of cancer on B2 is associated with a significantly decreased risk of volume-related but not grade-related progression. This must be considered when counseling men on AS.


Annals of Oncology | 2016

Tumor heterogeneity of fibroblast growth factor receptor 3 (FGFR3) mutations in invasive bladder cancer: implications for perioperative anti-FGFR3 treatment

Damien Pouessel; Y. Neuzillet; Laura S. Mertens; M. Van Der Heijden; J. De Jong; Joyce Sanders; Dennis Peters; Karen Leroy; A. Manceau; P. Maille; Pascale Soyeux; Anissa Moktefi; Fannie Semprez; D. Vordos; A. De La Taille; Carolyn D. Hurst; Darren C. Tomlinson; Patricia Harnden; P. J. Bostrom; Tuomas Mirtti; Simon Horenblas; Y. Loriot; Nadine Houede; Christine Chevreau; Philippe Beuzeboc; S.F. Shariat; Arthur I. Sagalowsky; Raheela Ashfaq; Maximilian Burger; Michael A.S. Jewett

BACKGROUNDnFibroblast growth factor receptor 3 (FGFR3) is an actionable target in bladder cancer. Preclinical studies show that anti-FGFR3 treatment slows down tumor growth, suggesting that this tyrosine kinase receptor is a candidate for personalized bladder cancer treatment, particularly in patients with mutated FGFR3. We addressed tumor heterogeneity in a large multicenter, multi-laboratory study, as this may have significant impact on therapeutic response.nnnPATIENTS AND METHODSnWe evaluated possible FGFR3 heterogeneity by the PCR-SNaPshot method in the superficial and deep compartments of tumors obtained by transurethral resection (TUR, n = 61) and in radical cystectomy (RC, n = 614) specimens and corresponding cancer-positive lymph nodes (LN+, n = 201).nnnRESULTSnWe found FGFR3 mutations in 13/34 (38%) T1 and 8/27 (30%) ≥T2-TUR samples, with 100% concordance between superficial and deeper parts in T1-TUR samples. Of eight FGFR3 mutant ≥T2-TUR samples, only 4 (50%) displayed the mutation in the deeper part. We found 67/614 (11%) FGFR3 mutations in RC specimens. FGFR3 mutation was associated with pN0 (P < 0.001) at RC. In 10/201 (5%) LN+, an FGFR3 mutation was found, all concordant with the corresponding RC specimen. In the remaining 191 cases, RC and LN+ were both wild type.nnnCONCLUSIONSnFGFR3 mutation status seems promising to guide decision-making on adjuvant anti-FGFR3 therapy as it appeared homogeneous in RC and LN+. Based on the results of TUR, the deep part of the tumor needs to be assessed if neoadjuvant anti-FGFR3 treatment is considered. We conclude that studies on the heterogeneity of actionable molecular targets should precede clinical trials with these drugs in the perioperative setting.


Clinical Cancer Research | 2017

A Phase II, Randomized, Open-Label Study of Neoadjuvant Degarelix versus LHRH Agonist in Prostate Cancer Patients Prior to Radical Prostatectomy

Rashid K. Sayyid; Andrew Evans; Karen Hersey; Ranjena Maloni; Antonio Hurtado-Coll; Girish Kulkarni; Antonio Finelli; Alexandre R. Zlotta; Robert J. Hamilton; Martin Gleave; Neil Fleshner

Purpose: Degarelix, a new gonadotropin-releasing hormone (GnRH) receptor antagonist with demonstrated efficacy as first-line treatment in the management of high-risk prostate cancer, possesses some theoretical advantages over luteinizing hormone–releasing hormone (LHRH) analogues in terms of avoiding “testosterone flare” and lower follicle-stimulating hormone (FSH) levels. We set out to determine whether preoperative degarelix influenced surrogates of disease control in a randomized phase II study. Experimental Design: Thirty-nine patients were randomly assigned to one of three different neoadjuvant arms: degarelix only, degarelix/bicalutamide, or LHRH agonist/bicalutamide. Treatments were given for 3 months before prostatectomy. Patients had localized prostate cancer and had chosen radical prostatectomy as primary treatment. The primary end point was treatment effect on intratumoral dihydrotestosterone levels. Results: Intratumoral DHT levels were higher in the degarelix arm than both the degarelix/bicalutamide and LHRH agonist/bicalutamide arms (0.87 ng/g vs. 0.26 ng/g and 0.23 ng/g, P < 0.01). No significant differences existed for other intratumoral androgens, such as testosterone and dehydroepiandrosterone. Patients in the degarelix-only arm had higher AMACR levels on immunohistochemical analysis (P = 0.01). Serum FSH levels were lower after 12 weeks of therapy in both degarelix arms than the LHRH agonist/bicalutamide arm (0.55 and 0.65 vs. 3.65, P < 0.01), and inhibin B levels were lower in the degarelix/bicalutamide arm than the LHRH agonist/bicalutamide arm (82.14 vs. 126.67, P = 0.02). Conclusions: Neoadjuvant degarelix alone, compared with use of LHRH agonist and bicalutamide, is associated with higher levels of intratumoral dihydrotestosterone, despite similar testosterone levels. Further studies that evaluate the mechanisms behind these results are needed. Clin Cancer Res; 23(8); 1974–80. ©2016 AACR.


The Journal of Urology | 2016

An Increase in Gleason 6 Tumor Volume While on Active Surveillance Portends a Greater Risk of Grade Reclassification with Further Followup

Maria Komisarenko; Lih-Ming Wong; Patrick O. Richard; Narhari Timilshina; A. Toi; Andrew Evans; Alexandre R. Zlotta; Girish Kulkarni; Robert J. Hamilton; Neil Fleshner; Antonio Finelli

PURPOSEnWe evaluated the relative risk of later grade reclassification and outcomes of patients in whom high volume Gleason 6 prostate cancer develops while on active surveillance.nnnMATERIALS AND METHODSnA prospectively maintained database was used to identify patients on active surveillance between 1998 and 2013. Tumor volume was assessed based on the number of positive cores and proportion of core involvement. The chi-square and Fisher exact tests were used for analysis as appropriate. The primary end point was the development of grade reclassification, defined as grade only and/or grade and volume at the event biopsy.nnnRESULTSnA total of 555 men met the study inclusion criteria. Mean followup was 46 months. Overall 70 patients demonstrated an increase in tumor volume at or after biopsy 2. Compared to those men never experiencing volume or grade reclassification, prostate specific antigen at diagnosis was not significantly different (p=0.95), but median prostate volume was smaller in patients who demonstrated volume reclassification (p <0.001). The incidence of pure volume reclassification was 6.8%, 6.1% and 7.8% at biopsy 2, 3 and 4, respectively. Men with volume reclassification were more likely to experience later grade reclassification than those without at 33.3% vs 9.3%, respectively (p <0.0001).nnnCONCLUSIONSnWhile Gleason 6 prostate cancer has a favorable natural history, it appears that patients on active surveillance who experience volume reclassification are at substantially higher risk for grade reclassification. Thus, urologists should pay close attention to tumor core involvement, and monitoring should be adjusted accordingly for early volume reclassification in younger men and those in good health.


Investigative and Clinical Urology | 2016

Treatment of bladder cancer in the elderly.

Annette Erlich; Alexandre R. Zlotta

As the population ages and life expectancy increases in the human population, more individuals will be diagnosed with bladder cancer (BC). The definition of who is elderly is likely to change in the future from the commonly used cut-off of ≥75 years of age. Physiological rather than chronological age is key. BC care in the elderly is likely to become a very common problem in daily practice. Concerns have been raised that senior BC patients are not given treatments that could cure their disease. Clinicians lack quantitative and reliable estimates of competing mortality risks when considering treatments for BC. Majority of patients diagnosed with BC are elderly, making treatment decisions complex with their increasing number of comorbidities. A multidisciplinary approach to these patients may be a way to incorporate discussion from various disciplines regarding treatment options available. Here we review various treatment options for elderly patients with muscle invasive BC and nonmuscle invasive BC. We include differences in treatments from robotic versus open radical cystectomy, various urinary diversion techniques, chemotherapy, radiation therapy and combination treatments. In clinical practice, treatment decisions for elderly patients should be done on a case-by-case basis, tailored to each patient with their specific histories and comorbidities considered. Some healthy elderly patients may be better candidates for extensive curative treatments than their younger counterparts. This implies that these important, life-altering decisions cannot be solely based on age as many other factors can affect patient survival outcomes.

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Neil Fleshner

Princess Margaret Cancer Centre

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Girish Kulkarni

Princess Margaret Cancer Centre

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Antonio Finelli

Princess Margaret Cancer Centre

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Robert J. Hamilton

Princess Margaret Cancer Centre

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Michael A.S. Jewett

Princess Margaret Cancer Centre

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Narhari Timilshina

Princess Margaret Cancer Centre

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Patrick O. Richard

Centre Hospitalier Universitaire de Sherbrooke

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