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Featured researches published by Casey K. Ng.


European Urology | 2010

A Comparison of Postoperative Complications in Open versus Robotic Cystectomy

Casey K. Ng; Eric C. Kauffman; Ming-Ming Lee; Brandon Otto; Alyse Portnoff; Josh R. Ehrlich; Michael Schwartz; Gerald J. Wang; Douglas S. Scherr

BACKGROUND Robotic cystectomy is an emerging alternative for treatment of invasive bladder cancer (BCa). However, reduction in postoperative morbidity relative to the open approach has not been demonstrated. OBJECTIVE To compare complication rates in patients undergoing robotic versus open radical cystectomy (RC). DESIGN, SETTING, AND PARTICIPANTS A prospective cohort study of 187 consecutive patients undergoing RC at our institution-104 open RC, 83 robotic RC. INTERVENTION Open or robotic RC with urinary diversion. MEASUREMENTS Demographic, perioperative, and complication data were recorded prospectively. Thirty-day and 90-d complication rates were assessed using the modified Clavien complication scale. Data were evaluated using chi(2) and multivariate logistic regression analyses. RESULTS AND LIMITATIONS At 30 d, the open group demonstrated a higher overall complication rate (59% vs 41%; p=0.04) as well as more major complications (30% vs 10%; p=0.007). At 90 d, the overall complication rate was greater in the open group, but this was not statistically significant (62% vs 48%; p=0.07). However, there was a significantly higher major complication rate in the open cohort (31% vs 17%; p=0.03). When subjected to logistic regression analysis, robotic cystectomy was an independent predictor of fewer overall and major complications at 30 and 90 d. High American Society of Anesthesiologists (ASA) score (3-4) and longer surgical time were independent predictors of major complications. Though this is one of the largest published RC series, the sample size is relatively small. Moreover, despite the two patient cohorts being similarly matched, the study was not performed in a randomized fashion. CONCLUSIONS Patients undergoing robotic cystectomy experienced fewer postoperative complications than those undergoing open cystectomy. Robotic cystectomy is an independent predictor of fewer overall and major complications. Until long-term oncologic results are available, robotic cystectomy should still be considered investigational.


The Journal of Urology | 2009

Adjuvant chemotherapy for high risk upper tract urothelial carcinoma: results from the Upper Tract Urothelial Carcinoma Collaboration.

Nicholas J. Hellenthal; Shahrokh F. Shariat; Vitaly Margulis; Pierre I. Karakiewicz; Marco Roscigno; Christian Bolenz; Mesut Remzi; Alon Z. Weizer; Richard Zigeuner; K. Bensalah; Casey K. Ng; Jay D. Raman; Eiji Kikuchi; Francesco Montorsi; Mototsugu Oya; Christopher G. Wood; Mario Fernandez; Christopher P. Evans; Theresa M. Koppie

PURPOSE There is relatively little literature on adjuvant chemotherapy after radical nephroureterectomy in patients with upper tract urothelial carcinoma. We determined the incidence of adjuvant chemotherapy in high risk patients and the ensuing effect on overall and cancer specific survival. MATERIALS AND METHODS Using an international collaborative database we identified 1,390 patients who underwent nephroureterectomy for nonmetastatic upper tract urothelial carcinoma between 1992 and 2006. Of these cases 542 (39%) were classified as high risk (pT3N0, pT4N0 and/or lymph node positive). These patients were divided into 2 groups, including those who did and did not receive adjuvant chemotherapy, and stratified by gender, age group, performance status, and tumor grade and stage. Cox proportional hazard modeling and Kaplan-Meier analysis were used to determine overall and cancer specific survival in the cohorts. RESULTS Of high risk patients 121 (22%) received adjuvant chemotherapy. Adjuvant chemotherapy was more commonly administered in the context of increased tumor grade and stage (p <0.001). Median survival in the entire cohort was 24 months (range 0 to 231). There was no significant difference in overall or cancer specific survival between patients who did and did not receive adjuvant chemotherapy. However, age, performance status, and tumor grade and stage were significant predictors of overall and cancer specific survival. CONCLUSIONS Adjuvant chemotherapy is infrequently used to treat high risk upper tract urothelial carcinoma after nephroureterectomy. Despite this finding it appears that adjuvant chemotherapy confers minimal impact on overall or cancer specific survival in this group.


The Journal of Urology | 2010

Preoperative Hydronephrosis, Ureteroscopic Biopsy Grade and Urinary Cytology Can Improve Prediction of Advanced Upper Tract Urothelial Carcinoma

James C. Brien; Shahrokh If. Shariat; Michael Herman; Casey K. Ng; Douglas S. Scherr; Benjamin Scoll; Robert G. Uzzo; Mark Wille; John D. Terrell; Steven M. Lucas; Yair Lotan; Stephen A. Boorjian; Jay D. Raman

PURPOSE We evaluated the value of hydronephrosis, ureteroscopic biopsy grade and urinary cytology to predict advanced upper tract urothelial carcinoma. MATERIALS AND METHODS We reviewed the charts of 469 patients with upper tract urothelial carcinoma treated with radical nephroureterectomy or distal ureterectomy. Complete data on hydronephrosis (present vs absent), ureteroscopic grade (high vs low) and urinary cytology (positive vs negative) were available in 172 patients. The outcome was muscle invasive (pT2-pT4) or nonorgan confined (pT3 or greater, or lymph node metastasis) upper tract urothelial carcinoma. RESULTS Of the patients 92 (54%) had hydronephrosis, 74 (43%) had high grade disease on ureteroscopic biopsy and 137 (80%) had positive cytology. On univariate analysis hydronephrosis (p <0.001), high ureteroscopic grade (p <0.001) and positive cytology (p = 0.03) were associated with muscle invasive and nonorgan confined disease. On multivariate analysis adjusting for tumor site, gender and age hydronephrosis and high ureteroscopic grade were associated with muscle invasive carcinoma (HR 12.0 and 4.5, respectively, each p <0.001) but cytology was not (HR 2.3, p = 0.17). However, all 3 variables were independently associated with nonorgan confined disease (HR 5.1, p <0.001; HR 3.9, p <0.001; and HR 3.1, p = 0.035, respectively). Combining these 3 tests incrementally improved the prediction of upper tract urothelial carcinoma stage. Abnormality of all 3 tests had 89% and 73% positive predictive value for muscle invasive and nonorgan confined upper tract urothelial carcinoma, respectively, but when all tests were normal, the negative predictive value was 100%. CONCLUSIONS Preoperative evaluation for hydronephrosis, ureteroscopic grade and cytology can identify patients at risk for advanced upper tract urothelial carcinoma. Such knowledge may impact surgery choice and extent as well as the need for perioperative chemotherapy regimens.


The Journal of Urology | 2011

Face, Content and Construct Validity of a Novel Robotic Surgery Simulator

Andrew J. Hung; Pascal Zehnder; Mukul Patil; Jie Cai; Casey K. Ng; Monish Aron; Inderbir S. Gill; Mihir M. Desai

PURPOSE We evaluated the face, content and construct validity of the novel da Vinci® Skills Simulator™ using the da Vinci Si™ Surgeon Console as the surgeon interface. MATERIALS AND METHODS We evaluated a novel robotic surgical simulator for robotic surgery using the da Vinci Si Surgeon Console and Mimic™ virtual reality. Subjects were categorized as novice-no surgical training, intermediate-surgical training with fewer than 100 robotic cases or expert-100 or more primary surgeon robotic cases. Each participant completed 10 virtual reality exercises with 3 repetitions and a questionnaire with a 1 to 10 visual analog scale to assess simulator realism (face validity) and training usefulness (content validity). The simulator recorded performance based on specific metrics. The performance of experts, intermediates and novices was compared (construct validity) using the Kruskal-Wallis test. RESULTS We studied 16 novices, 32 intermediates with a median surgical experience of 6 years (range 1 to 37) and a median of 0 robotic cases (range 0 to 50), and 15 experts with a median of 315 robotic cases (range 100 to 800). Participants rated the virtual reality and console experience as very realistic (median visual analog scale score 8/10) while expert surgeons rated the simulator as a very useful training tool for residents (10/10) and fellows (9/10). Experts outperformed intermediates and novices in almost all metrics (median overall score 88.3% vs 75.6% and 62.1%, respectively, between group p<0.001). CONCLUSIONS We confirmed the face, content and construct validity of a novel robotic skill simulator that uses the da Vinci Si Surgeon Console. Although it is currently limited to basic skill training, this device is likely to influence robotic surgical training across specialties.


The Journal of Urology | 2009

Impact of Lymph Node Dissection on Cancer Specific Survival in Patients With Upper Tract Urothelial Carcinoma Treated With Radical Nephroureterectomy

Marco Roscigno; Shahrokh F. Shariat; Vitaly Margulis; Pierre I. Karakiewicz; Mesut Remzi; Eiji Kikuchi; Cord Langner; Yair Lotan; Alon Z. Weizer; K. Bensalah; Jay D. Raman; Christian Bolenz; Charles C. Guo; Christopher G. Wood; Richard Zigeuner; Jeffrey Wheat; Wareef Kabbani; Theresa M. Koppie; Casey K. Ng; Nazareno Suardi; Roberto Bertini; Mario Fernandez; Shuji Mikami; Masaru Isida; Maurice Stephan Michel; Francesco Montorsi

PURPOSE We examined the impact of lymphadenectomy on the clinical outcomes of patients with upper tract urothelial cancer treated with radical nephroureterectomy. MATERIALS AND METHODS Data were collected on 1,130 consecutive patients with pT1-4 upper tract urothelial cancer treated with radical nephroureterectomy at 13 centers worldwide. Patients were grouped according to nodal status (pN0 vs pNx vs pN+). The choice to perform lymphadenectomy was determined by the treating surgeon. All pathology slides were reevaluated by dedicated genitourinary pathologists. Univariable and multivariable Cox regression models measured the association of nodal status (pN0 vs pNx vs pN+) with cancer specific survival. RESULTS Overall 412 patients (36.5%) had pN0 disease, 578 had pNx disease (51.1%) and 140 had pN+ disease (12.4%). The 5-year cancer specific survival estimate was lower in patients with pN+ compared to those with pNx disease (35% vs 69%, p <0.001), which in turn was lower than that in those with pN0 disease (69% vs 77%, p = 0.024). In the subgroup of patients with pT1 disease (345) cancer specific survival rates were not different in those with pN0 and pNx. In pT2-4 cases (813) cancer specific survival estimates were lowest in pN+, intermediate in pNx and highest in pN0 (33% vs 58% vs 70%, p = 0.017). When adjusted for the effects of standard clinicopathological features pN+ was an independent predictor of cancer specific survival (p <0.001). pNx was significantly associated with worse prognosis than pN0 in pT2-4 upper tract urothelial cancer only. CONCLUSIONS Nodal status is a significant predictor of cancer specific survival in upper tract urothelial cancer. pNx is significantly associated with a worse prognosis than pN0 in pT2-4 tumors. Patients expected to have pT2-4 disease should undergo lymphadenectomy to improve staging and thereby help guide decision making regarding adjuvant chemotherapy.


European Urology | 2010

Impact of Tumor Location on Prognosis for Patients with Upper Tract Urothelial Carcinoma Managed by Radical Nephroureterectomy

Jay D. Raman; Casey K. Ng; Douglas S. Scherr; Vitaly Margulis; Yair Lotan; K. Bensalah; Jean Jacques Patard; Eiji Kikuchi; Francesco Montorsi; Richard Zigeuner; Alon Z. Weizer; Christian Bolenz; Theresa M. Koppie; Hendrik Isbarn; Claudio Jeldres; Wareef Kabbani; Mesut Remzi; Mathias Waldert; Christopher G. Wood; Marco Roscigno; Mototsuga Oya; Cord Langner; J. Stuart Wolf; Philipp Ströbel; Mario Fernandez; Pierre Karakiewcz; Shahrokh F. Shariat

BACKGROUND There is a lack of consensus regarding the prognostic significance of ureteral versus renal pelvic upper tract urothelial carcinoma (UTUC). OBJECTIVE To investigate the association of tumor location on outcomes for UTUC in an international cohort of patients managed by radical nephroureterectomy (RNU). DESIGN, SETTING, AND PARTICIPANTS A retrospective review of institutional databases from 10 institutions worldwide identified patients with UTUC. INTERVENTION The 1249 patients in the study underwent RNU with ipsilateral bladder cuff resection between 1987 and 2007. MEASUREMENTS Data accrued included age, gender, race, surgical approach (open vs laparoscopic), tumor pathology (stage, grade, lymph node status), tumor location, use of perioperative chemotherapy, prior endoscopic therapy, urothelial carcinoma recurrence, and mortality from urothelial carcinoma. Tumor location was divided into two groups (renal pelvis and ureter) based on the location of the dominant tumor. RESULTS AND LIMITATIONS The 5-yr recurrence-free and cancer-specific survival estimates for this cohort were 75% and 78%, respectively. On multivariate analysis, only pathologic tumor (pT) classification (p<0.001), grade (p<0.02), and lymph node status (p<0.001) were associated with disease recurrence and cancer-specific survival. When adjusting for these variables, there was no difference in the probability of disease recurrence (hazard ratio [HR]: 1.22; p=0.133) or cancer death (HR: 1.23; p=0.25) between ureteral and renal pelvic tumors. Adding tumor location to a base prognostic model for disease recurrence and cancer death that included pT stage, tumor grade, and lymph node status only improved the predictive accuracy of this model by 0.1%. This study is limited by biases associated with its retrospective design. CONCLUSIONS There is no difference in outcomes between patients with renal pelvic tumors and with ureteral tumors following nephroureterectomy. These data support the current TNM staging system, whereby renal pelvic and ureteral carcinomas are classified as one integral group of tumors.


European Urology | 2009

The extent of lymphadenectomy seems to be associated with better survival in patients with nonmetastatic upper-tract urothelial carcinoma: how many lymph nodes should be removed?

Marco Roscigno; Shahrokh F. Shariat; Vitaly Margulis; Pierre I. Karakiewicz; Mesut Remzi; Eiji Kikuchi; Richard Zigeuner; Alon Z. Weizer; Arthur I. Sagalowsky; K. Bensalah; Jay D. Raman; Christian Bolenz; Wassim Kassou; Theresa M. Koppie; Christopher G. Wood; Jeffrey Wheat; Cord Langner; Casey K. Ng; Umberto Capitanio; Roberto Bertini; Mario Fernandez; Shuji Mikami; Masaru Isida; Philipp Ströbel; Francesco Montorsi

BACKGROUND The role and extent of lymphadenectomy in patients with upper-tract urothelial carcinoma (UTUC) is debated. OBJECTIVE To establish whether the number of lymph nodes (LNs) removed might be associated with better cause-specific survival in patients with UTUC. DESIGN, SETTING, AND PARTICIPANTS The study included 552 consecutive patients who underwent radical nephroureterectomy (RNU) and lymphadenectomy between 1992 and 2006. INTERVENTION Patients were treated with RNU and lymphadenectomy. MEASUREMENTS Univariable and multivariable Cox proportional hazards regression models addressed the association between the number of LNs removed and cause-specific mortality (CSM). The number of LNs removed was coded as a cubic spline to allow for nonlinear effects. Finally, the most informative cut-off for the number of removed LNs was identified. RESULTS AND LIMITATIONS In the entire population, the number of LNs removed was not associated with CSM in univariable (hazard ratio [HR]: 0.99; p=0.16) or in multivariable (HR: 0.97; p=0.12) analyses. In contrast, in the subgroup of pN0 patients (n=412), the number of LNs removed achieved the independent predictor status of CSM (HR: 0.93; p=0.02). Eight LNs removed was the most informative cut-off in predicting CSM (HR: 0.42; p=0.004). The inclusion of the variable defining dichotomously the number of removed LNs (< 8 vs > or = 8) in the base model (age, Eastern Cooperative Oncology Group performance status, pathologic stage, grade, architecture, and lymphovascular invasion) significantly increased the accuracy in predicting CSM (+1.7%; p<0.001). CONCLUSIONS The extension of the lymphadenectomy in pN0 UTUC patients seems to be associated with CSM. Longer survival was observed in patients in whom at least eight LNs had been removed.


European Urology | 2012

Predicting Clinical Outcomes After Radical Nephroureterectomy for Upper Tract Urothelial Carcinoma

Eugene K. Cha; Shahrokh F. Shariat; Matthias Kormaksson; Giacomo Novara; Thomas F. Chromecki; Douglas S. Scherr; Yair Lotan; Jay D. Raman; Wassim Kassouf; Richard Zigeuner; Mesut Remzi; Karim Bensalah; Alon Z. Weizer; Eiji Kikuchi; Christian Bolenz; Marco Roscigno; Theresa M. Koppie; Casey K. Ng; Hans Martin Fritsche; Kazumasa Matsumoto; Thomas J. Walton; Behfar Ehdaie; Stefan Tritschler; Harun Fajkovic; Juan I. Martínez-Salamanca; Armin Pycha; Cord Langner; Vincenzo Ficarra; Jean Jacques Patard; Francesco Montorsi

BACKGROUND Novel prognostic factors for patients after radical nephroureterectomy (RNU) for upper tract urothelial carcinoma (UTUC) have recently been described. OBJECTIVE We tested the prognostic value of pathologic characteristics and developed models to predict the individual probabilities of recurrence-free survival (RFS) and cancer-specific survival (CSS) after RNU. DESIGN, SETTING, AND PARTICIPANTS Our study included 2244 patients treated with RNU without neoadjuvant or adjuvant therapy at 23 international institutions. Tumor characteristics included T classification, grade, lymph node status, lymphovascular invasion, tumor architecture, location, and concomitant carcinoma in situ (CIS). The cohort was randomly split for development (12 centers, n=1273) and external validation (11 centers, n=971). INTERVENTIONS All patients underwent RNU. MEASUREMENTS Univariable and multivariable models addressed RFS, CSS, and comparison of discrimination and calibration with American Joint Committee on Cancer (AJCC) stage grouping. RESULTS AND LIMITATIONS At a median follow-up of 45 mo, 501 patients (22.3%) experienced disease recurrence and 418 patients (18.6%) died of UTUC. On multivariable analysis, T classification (p for trend <0.001), lymph node metastasis (hazard ratio [HR]: 1.98; p=0.002), lymphovascular invasion (HR: 1.66; p<0.001), sessile tumor architecture (HR: 1.76; p<0.001), and concomitant CIS (HR: 1.33; p=0.035) were associated with disease recurrence. Similarly, T classification (p for trend<0.001), lymph node metastasis (HR: 2.23; p=0.001), lymphovascular invasion (HR: 1.81; p<0.001), and sessile tumor architecture (HR: 1.72; p=0.001) were independently associated with cancer-specific mortality. Our models achieved 76.8% and 81.5% accuracy for predicting RFS and CSS, respectively. In contrast to these well-calibrated models, stratification based upon AJCC stage grouping resulted in a large degree of heterogeneity and did not improve discrimination. CONCLUSIONS Using standard pathologic features, we developed highly accurate prognostic models for the prediction of RFS and CSS after RNU for UTUC. These models offer improvements in calibration over AJCC stage grouping and can be used for individualized patient counseling, follow-up scheduling, risk stratification for adjuvant therapies, and inclusion criteria for clinical trials.


BJUI | 2009

Tumour architecture is an independent predictor of outcomes after nephroureterectomy: a multi‐institutional analysis of 1363 patients

Mesut Remzi; Andrea Haitel; Vitaly Margulis; Pierre Karakiewizc; Francesco Montorsi; Eiji Kikuchi; Richard Zigeuner; Alon Z. Weizer; Christian Bolenz; K. Bensalah; Nazareno Suardi; Jay D. Raman; Yair Lotan; Matthias Waldert; Casey K. Ng; Mario Fernandez; Theresa M. Koppie; Philipp Ströbel; Wareef Kabbani; Masaru Murai; Cord Langner; Marco Roscigno; Jeffrey Wheat; Charles C. Guo; Christopher G. Wood; Shahrokh F. Shariat

To assess whether tumour architecture can help to refine the prognosis of patients treated with nephroureterectomy (NU) for urothelial carcinoma (UC) of the upper urinary tract (UT), as the prognostic value of tumour architecture (papillary vs sessile) in UTUC remains elusive.


BJUI | 2005

Bladder cancer after managing upper urinary tract transitional cell carcinoma: predictive factors and pathology

Jay D. Raman; Casey K. Ng; Stephen A. Boorjian; E. Darracott Vaughan; R. Ernest Sosa; Douglas S. Scherr

To evaluate patients with a history of transitional cell carcinoma (TCC) of the upper urinary tract (UUT) to determine the incidence, pathological distribution, and risk factors for developing subsequent bladder tumours.

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Shahrokh F. Shariat

Medical University of Vienna

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Jay D. Raman

Penn State Milton S. Hershey Medical Center

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Yair Lotan

University of Texas Southwestern Medical Center

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Vitaly Margulis

University of Texas Southwestern Medical Center

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Francesco Montorsi

Vita-Salute San Raffaele University

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Marco Roscigno

Vita-Salute San Raffaele University

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