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Dive into the research topics where Nader Fahmy is active.

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Featured researches published by Nader Fahmy.


The Journal of Urology | 2006

Effect of Preoperative Delay on Survival in Patients With Bladder Cancer Undergoing Cystectomy in Quebec: A Population Based Study

Salaheddin M. Mahmud; Brian C. Fong; Nader Fahmy; Simon Tanguay; Armen Aprikian

PURPOSE In Canada there is growing concern that waiting time for cancer surgery has been increasing. We used population based data to estimate the average PD for RC in Quebec and assess whether delayed surgery has a negative impact on long-term survival. MATERIALS AND METHODS We used the provincial billing database of the maladie du Quebec to identify all patients with bladder cancer 18 years or older who underwent RAMQ from 1990 to 2002. PD was calculated as the time elapsed between the most recent transurethral resection and the date of RC. Patients were categorized according to PD tertiles into 3 groups, namely 1) 20 or less, 2) 21 to 47 and (C) 48 days or greater. Cox proportional hazards models were used to assess the effect of PD on overall survival, while adjusting for patient and provider factors. RESULTS During the study period 1,592 radical cystectomies were performed. Overall median PD was 33 days (95% CI 30 to 35). Median PD increased from 23 days in 1990 to 50 in 2002. After adjusting for calendar year, and patient and provider variables there were no significant differences in survival among the 3 delay categories. However, patients subject to greater than 12 weeks of delay were at 20% greater risk for dying (95% CI 1.0 to 1.5, p = 0.051). CONCLUSIONS In line with previous reports PD greater than 12 weeks seems to be associated with a worse long-term prognosis.


Cancer | 2008

Role of repeated biopsy of the prostate in predicting disease progression in patients with prostate cancer on active surveillance

Mohammed Al Otaibi; Philip Ross; Nader Fahmy; Suganthiny Jeyaganth; Helen Trottier; Kanishka Sircar; Louis R. Bégin; Luis Souhami; Wassim Kassouf; Armen Aprikian; Simon Tanguay

Active surveillance (AS) with deferred treatment is an established management option for patients with prostate cancer and favorable clinical parameters. The impact of repeat biopsy after diagnosis was examined in a cohort of men with prostate cancer on AS.


Human Reproduction | 2011

Antisperm antibodies are not associated with pregnancy rates after IVF and ICSI: systematic review and meta-analysis

Armand Zini; Nader Fahmy; Eric Belzile; Antonio Ciampi; Naif Alhathal; Ahmed Kotb

BACKGROUND Several studies have examined the relationship between direct antisperm antibody (ASA) levels in semen and pregnancy rate after advanced assisted reproductive technologies (ARTs) but the results have been inconsistent. The aim of our study was to further evaluate the relationship between ASA and pregnancy after IVF or ICSI by systematic review and meta-analysis. METHODS We conducted a systematic Medline search of all relevant full papers on direct semen ASA and pregnancy after IVF or ICSI. Three investigators independently reviewed the papers, followed by group discussion to choose the included papers. Meta-analysis was performed to get an odds ratio (OR) for the effect of ASA on pregnancy using IVF or ICSI. RESULTS The study identified and analyzed 16 valid studies (10 IVF and 6 ICSI). The study characteristics (including the ASA cutoff values) were heterogeneous. Our meta-analysis revealed that the combined OR for failure to achieve a pregnancy using IVF or ICSI in the presence of positive semen ASA was 1.22 (95% CI: 0.84, 1.77) and 1.00 (95% CI: 0.72, 1.38), respectively. The overall (IVF + ICSI) combined OR was 1.08 (95% CI: 0.85, 1.38). CONCLUSION This systematic review and meta-analysis indicate that semen antisperm antibodies are not related to pregnancy rates after IVF or ICSI, suggesting that both forms of ART remain viable options for infertile couples with semen ASA. However, additional, well-designed prospective studies using appropriate ASA cutoff levels are needed to further address this issue.


Urologia Internationalis | 2010

Outcome of Surgical Treatment of Patients with Upper versus Lower Urinary Tract Urothelial Carcinoma: Stage-by-Stage Comparison

S. Moussa; Faysal A. Yafi; Assaad El-Hakim; Nader Fahmy; Armen Aprikian; Simon Tanguay; M. Anidjar; Wassim Kassouf

Objectives: It remains controversial whether we can apply similar principles in the management of upper urinary tract urothelial carcinoma (UUT-UC) based on the behavior of bladder urothelial carcinoma (B-UC). We sought to assess whether UUT-UC and B-UC have similar biology and performed a stage-by-stage comparative analysis of outcome between the 2 groups. Methods: A retrospective review was performed on patients who underwent nephroureterectomy for UUT-UC and radical cystectomy for B-UC from 1991 to 2006. Standard variables were collected and recurrence-free and overall survival (OS) rates were calculated. Results: 280 patients with a median age of 69 years were included (99 UUT-UC treated via nephroureterectomy and 181 B-UC treated via radical cystectomy). Median follow-up was 29 months. None received neoadjuvant chemotherapy. Patients with UUT-UC presented less commonly with invasive disease compared to those with B-UC (44 vs. 77% were >pT2). Overall, 5-year OS for the B-UC group was significantly lower than for the UUT-UC group (60.8 vs. 74.5%, p = 0.02). However, when patients were stratified by stage (>pT2), patients with B-UC had similar OS compared to those with UUT-UC (54.6 vs. 60.8%, p = 0.74). Conclusion: Invasive UUT-UC appears to have similar tumor biology compared to B-UC. Whether we can safely extrapolate on the benefit of neoadjuvant and adjuvant strategies to patients with UUT-UC requires further investigation.


Cuaj-canadian Urological Association Journal | 2015

Assessment of photoselective vaporization of prostate skills during Urology Objective Structured Clinical Examinations (OSCE)

Yasser A. Noureldin; Mohamed A. Elkoushy; Nader Fahmy; Serge Carrier; Mostafa M. Elhilali; Sero Andonian

INTRODUCTION We evaluated the use of the GreenLight Simulator (GL-SIM) (American Medical Systems, Guelph, ON) in the skill assessment of postgraduate trainees (PGTs) in photoselective vaporization of the prostate (PVP). We also sought to determine whether previous PVP experience or GL-SIM practice improved performance. METHODS PGTs in postgraduate years (PGY-3 to PGY-5) from all 4 Quebec urology training programs were recruited during 2 annual Objective Structured Clinical Examinations (OSCEs). During a 20-minute OSCE station, PGTs were asked to perform 2 exercises: (1) identification of endoscopic landmarks and (2) a PVP of a 30-g normal prostate. Grams vaporized, global scores, and number of correct anatomical landmarks were recorded and correlated with PGY level, practice on the GL-SIM, and previous PVP experience. RESULTS In total, 25 PGTs were recruited at each OSCE, with 13 PGTs participating in both OSCEs. When comparing scores from the first and second OSCEs, there was a significant improvement in the number of grams vaporized (2.9 vs. 4.3 g; p = 0.003) and global score (100 vs. 165; p = 0.03). There was good correlation between the number of previously performed PVPs and the global score (r = 0.4, p = 0.04). Similarly, PGTs with previous practice on the GL-SIM had significantly higher global score (100.6 vs. 162.6; p = 0.04) and grams vaporized (3.1 vs. 4.1 g; p = 0.04) when compared with those who did not practice on GL-SIM. Furthermore, there were significantly more competent PGTs among those who had previously practiced on the GL-SIM (32.7% vs. 10.2%; p = 0.009). PGY level did not significantly affect grams vaporized or global score (p > 0.05). CONCLUSION Performance on the GL-SIM at OSCEs significantly correlated with previous practice on the GL-SIM and previous PVP experience rather than PGY level. Furthermore, there were significantly more competent PGTs among those who had previously practiced on the GL-SIM.


Cuaj-canadian Urological Association Journal | 2013

Effect of anticoagulants and antiplatelet agents on the efficacy of intravesical BCG treatment of bladder cancer: A systematic review

Nader Fahmy; Alejandro Lazo-Langner; Alla E. Iansavichene; Stephen E. Pautler

We performed a systematic review of publications describing a correlation between oral anticoagulant medications and intravesical BCG outcome. We collected information on the impact of such medications on tumour recurrence and progression and we excluded papers not reporting outcome correlations. Patients were divided into group 1 and 2 based on whether they were taking or not taking any anticoagulant medications. A total of 7 manuscripts published between 1990 and 2009 were included in this study. Data heterogeneity precluded meta-analysis. In studies combining all anticoagulant medications, 3 out of 5 (60%) publications did not identify any difference in outcome, while 2 (40%) documented significantly more recurrences in group 1 patients. In studies performing multivariate analysis and only examining the intake of 1 medication, warfarin alone seemed to be associated with increased risk of bladder tumour recurrences and progression following intravesical BCG treatment, while ASA alone seemed to be associated with more protective effects. There is no strong evidence to support the allegations of a protective role of ASA and a deleterious role for warfarin. Further, well-designed experimental and clinical studies are needed to clarify the mechanism of action of intravesical BCG along with possible drug interactions.


Cuaj-canadian Urological Association Journal | 2014

Endogenous biotin expression in renal and testicular tumors and literature review

Nader Fahmy; Mark Woo; Mona Alameldin; King Chien Joe Lee; Kyle MacDonald; Lee W. Goneau; Peter A. Cadieux; Jeremy P. Burton; Stephen E. Pautler

INTRODUCTION The aim of this study was to examine endogenous biotin levels in tumour specimens collected from patients with renal and testicular tumours and compare them to the surrounding non-neoplastic surgical margin. METHODS Frozen samples were obtained from the Ontario Tumour Bank. Renal and testicular tumour tissue were included in this study. Normal tissue from the negative surgical margins of each tumour served as a control. Biotin detection in tissue specimens was determined using immunohistochemistry (IHC). RESULTS Specimens collected from 56 patients (36 men and 20 women) were included in this study. Histopathology of the 52 renal tumours included 31 (60%) conventional type RCC, 5 (10%) chromophobe RCC, 5 (10%) papillary RCC, 1 (2%) oncocytoma and 10 (19%) upper tract urothelial carcinoma (UC). The 4 testicular tumours included 1 seminomatous (25%) germ cell tumour and 3 (75%) non seminomatous germ cell tumours. CONCLUSION No biotin signal was perceived in all tested tumour samples. Endogenous biotin expression was detected in the matching non-neoplastic surgical margin of tested renal tissues. This lack of staining may prove to be a valuable tool in future studies.


Cuaj-canadian Urological Association Journal | 2014

Ochratoxin A is not detectable in renal and testicular tumours

Nader Fahmy; Mark Woo; Mona Alameldin; Kyle MacDonald; Lee W. Goneau; Peter A. Cadieux; Stephen E. Pautler

INTRODUCTION Ochratoxin-A (OTA) is one of the most abundant food-contaminating mycotoxins, known for its nephrotoxicity, neurotoxicity, gonadotoxicity, teratogenicity, immunosuppression and carcinogenesis. OTA has been linked to several genitourinary pathologies, including Balkan nephropathy and genitourinary malignancies. We examine OTA levels in serum samples and tumour specimens collected from patients with renal and testicular tumours. METHODS Frozen samples were obtained from the Ontario Tumour Bank. Serum specimens, along with renal and testicular tumour biopsies, were included in this study. Normal tissue from the negative surgical margins of each tumour served as a control. OTA levels in serum was measured using the enzyme-linked immunosorbent assay (ELISA), while OTA detection in tissue specimens was determined using immunohistochemistry (IHC). RESULTS We included specimens collected from 56 patients (36 men and 20 women). Histopathology of the 52 renal tumours included 31 (60%) conventional type renal cell carcinomas (RCC), 5 (10%) chromophobe RCC, 5 (10%) papillary RCC, 1 (2%) oncocytoma and 10 (19%) upper tract urothelial carcinoma (UC). The 4 testicular tumours included 1 seminomatous (25%) germ cell tumour and 3 (75%) non-seminomatous germ cell tumours. OTA was detected in the serum of renal tumour patients, with a range from 0.004 to 0.25 ng/mL (mean: 0.07 and median 0.06 ng/mL). There was no OTA signal detected by IHC staining in all tested renal and testicular tumours. CONCLUSIONS The OTA levels detected in the serum of patients were highly variable and relatively low. No OTA was detected in the tissue samples.


Türk Üroloji Dergisi/Turkish Journal of Urology | 2017

Is it safe to prescribe ascorbic acid for urinary acidification in stone-forming patients with alkaline urine?

Yasser A. Noureldin; Alexandrine da Silva; Nader Fahmy; Sero Andonian

OBJECTIVE To study the effect of ascorbic acid (AA) supplementation on urinary pH, metabolic stone workup parameters, and development of de novo urolithiasis in stone-forming patients. MATERIAL AND METHODS A retrospective review of the patients followed-up at a tertiary stone centre between September 2009 and October 2015 was performed. Patients with recurrent urolithiasis who received AA supplementation as a urinary acidifying agent were included in the study. Detailed metabolic stone work-up, including two 24-hour urine collections obtained pre- and post-AA supplementation were compared. In addition, imaging studies were reviewed to assess the development of de novo urolithiasis. RESULTS Twenty-four patients were included in the study with a mean age of 60.6 years and a median daily AA dose of 1000 mg (range: 500-2000 mg). Median follow-up period was 22.6 months (range: 19.7-32.1). After AA supplementation, there was a significant decrease in urinary pH (7.6 vs. 6.9, p=0.02). Although there was no significant increase in the daily oxalate excretion, two patients (8.3%) had their AA dose reduced or discontinued due to de novo hyperoxaluria (342.9 vs 510.2 umol/day; p=0.75). Other serum and urinary parameters did not show any significant changes. Eight (33.3%) patients developed de novo urolithiasis with struvite and carbonate apatite being the major components. CONCLUSION AA supplementation resulted in significantly lower urinary pH in patients with recurrent urolithiasis and alkaline urine pH. Prospective studies are needed to assess whether this reduction in urinary pH is associated with lower stone recurrence rates.


Cuaj-canadian Urological Association Journal | 2017

Assessment of urology postgraduate trainees’ competencies in flexible ureteroscopic stone extraction

Mehdi Aloosh; Félix Couture; Nader Fahmy; Mostafa M. Elhilali; Sero Andonian

INTRODUCTION We aimed to assess flexible ureteroscopic stone extraction skill of urology postgraduate trainees (PGTs) at an Objective Structured Clinical Examination (OSCE) and to determine whether previous experience in the operating theatre or practice on the simulator correlated with performance. METHODS After obtaining ethics approval, PGTs from postgraduate years (PGYs) 3-5 were recruited from all four Quebec urology training programs during an OSCE. After a short orientation to the UroMentor™ simulator, PGTs were asked to perform Task 10 for 15 minutes, where two small stones from the left proximal ureter and renal pelvis were extracted using a basket. Competency of PGTs in performing the task was assessed using objective assessment from the simulator and subjective evaluations using Ureteroscopy-Global Rating Scale (URS-GRS). Simulator performance reports and URS-GRS scores were analyzed. RESULTS Thirty PGTs (9 PGY-3, 11 PGY-4, 10 PGY-5) participated in this study. PGTs had performed a mean of 55.9 semi-rigid and 45.7 flexible ureteroscopies prior to the study. Mean URS-GRS score of the participants was 20.0±4.4. Using norm-referenced method with three experts, cutoff score of 19 on the URS-GRS was determined to indicate competency. Sixty percent (18/30) of PGTs were competent. All eight PGTs who had practiced on the simulator were competent. Previous experience in the operating theatre and PGY level did not correlate with performance. CONCLUSIONS This study confirmed the feasibility of incorporating the UroMentor at OSCEs to assess competency of urology PGTs in ureteroscopic stone extraction skill. PGTs who practiced on the simulator scored significantly higher than those who did not practice; however, the software needs to be updated to improve its face validity and to include more complex tasks, such as holmium laser lithotripsy. Future studies with larger sample sizes and more complex cases are needed to confirm these results.

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Armen Aprikian

McGill University Health Centre

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Sero Andonian

McGill University Health Centre

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