Matthew E. Nielsen
University of North Carolina at Chapel Hill
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European Urology | 2010
Jeff Nix; Angela B. Smith; Raj Kurpad; Matthew E. Nielsen; Eric Wallen; Raj S. Pruthi
BACKGROUND In recent years, surgeons have begun to report case series of minimally invasive approaches to radical cystectomy, including robotic-assisted techniques demonstrating the surgical feasibility of this procedure with the potential of lower blood loss and more rapid return of bowel function and hospital discharge. Despite these experiences and observations, at this point high levels of clinical evidence with regard to the benefits of robotic cystectomy are absent, and the current experiences represent case series with limited comparisons to historical controls at best. OBJECTIVE We report our results on a prospective randomized trial of open versus robotic-assisted laparoscopic radical cystectomy with regard to perioperative outcomes, complications, and short-term narcotic usage. DESIGN, SETTING, AND PARTICIPANTS A prospective randomized single-center noninferiority study comparing open versus robotic approaches to cystectomy in patients who are candidates for radical cystectomy for urothelial carcinoma of the bladder. Of the 41 patients who underwent surgery, 21 were randomized to the robotic approach and 20 to the open technique. INTERVENTION Radical cystectomy, bilateral pelvic lymphadenectomy, and urinary diversion by either an open approach or by a robotic-assisted laparoscopic technique. MEASUREMENTS The primary end point was lymph node (LN) yield with a noninferiority margin of four LNs. Secondary end points included demographic characteristics, perioperative outcomes, pathologic results, and short-term narcotic use. RESULTS AND LIMITATIONS On univariate analysis, no significant differences were found between the two groups with regard to age, sex, body mass index, American Society of Anesthesiologists classification, anticoagulation regimen of aspirin, clinical stage, or diversion type. Significant differences were noted in operating room time, estimated blood loss, time to flatus, time to bowel movement, and use of inpatient morphine sulfate equivalents. There was no significant difference in regard to overall complication rate or hospital stay. On surgical pathology, in the robotic group 14 patients had pT2 disease or higher; 3 patients had pT3/T4 disease; and 4 patients had node-positive disease. In the open group, eight patients had pT2 disease or higher; five patients had pT3/T4 disease; and seven patients had node-positive disease. The mean number of LNs removed was 19 in the robotic group versus18 in the open group. Potential study limitations include the limited clinical and oncologic follow-up and the relatively small and single-institution nature of the study. CONCLUSIONS We present the results of a prospective randomized controlled noninferiority study with a primary end point of LN yield, demonstrating the robotic approach to be noninferior to the open approach. The robotic approach also compares favorably with the open approach in several perioperative parameters.
Genes & Cancer | 2010
A. Rose Brannon; Anupama Reddy; Michael Seiler; Alexandra Arreola; Dominic T. Moore; Raj S. Pruthi; Eric Wallen; Matthew E. Nielsen; Huiqing Liu; Katherine L. Nathanson; Börje Ljungberg; Hongjuan Zhao; James D. Brooks; Shridar Ganesan; Gyan Bhanot; W.Kimryn Rathmell
Clear cell renal cell carcinoma (ccRCC) is the predominant RCC subtype, but even within this classification, the natural history is heterogeneous and difficult to predict. A sophisticated understanding of the molecular features most discriminatory for the underlying tumor heterogeneity should be predicated on identifiable and biologically meaningful patterns of gene expression. Gene expression microarray data were analyzed using software that implements iterative unsupervised consensus clustering algorithms to identify the optimal molecular subclasses, without clinical or other classifying information. ConsensusCluster analysis identified two distinct subtypes of ccRCC within the training set, designated clear cell type A (ccA) and B (ccB). Based on the core tumors, or most well-defined arrays, in each subtype, logical analysis of data (LAD) defined a small, highly predictive gene set that could then be used to classify additional tumors individually. The subclasses were corroborated in a validation data set of 177 tumors and analyzed for clinical outcome. Based on individual tumor assignment, tumors designated ccA have markedly improved disease-specific survival compared to ccB (median survival of 8.6 vs 2.0 years, P = 0.002). Analyzed by both univariate and multivariate analysis, the classification schema was independently associated with survival. Using patterns of gene expression based on a defined gene set, ccRCC was classified into two robust subclasses based on inherent molecular features that ultimately correspond to marked differences in clinical outcome. This classification schema thus provides a molecular stratification applicable to individual tumors that has implications to influence treatment decisions, define biological mechanisms involved in ccRCC tumor progression, and direct future drug discovery.
The Journal of Urology | 2010
Raj S. Pruthi; Matthew E. Nielsen; Jeff Nix; Angela B. Smith; Heather Schultz; Eric Wallen
PURPOSE Radical cystectomy remains the most effective treatment for patients with localized, invasive bladder cancer and recurrent noninvasive disease. Recently some surgeons have begun to describe outcomes associated with less invasive surgical approaches to this disease such as laparoscopic or robotic assisted techniques. We report our maturing experience with 100 consecutive cases of robotic assisted laparoscopic radical cystectomy with regard to perioperative results, pathological outcomes and surgical complications. MATERIALS AND METHODS A total of 100 consecutive patients (73 male and 27 female) underwent robotic radical cystectomy and urinary diversion at our institution from January 2006 to January 2009 for clinically localized bladder cancer. Outcome measures evaluated included operative variables, hospital recovery, pathological outcomes and complication rate. RESULTS Mean age of this cohort was 65.5 years (range 33 to 86). Of the patients 61 underwent ileal conduit diversion, 38 received a neobladder and 1 had no urinary diversion (renal failure). Mean operating room time for all patients was 4.6 hours (median 4.3) and mean surgical blood loss was 271 ml (median 250). On surgical pathology 40% of the cases were pT1 or less disease, 27% were pT2, 13% were pT3/T4 disease and 20% were node positive. Mean number of lymph nodes removed was 19 (range 8 to 40). In no case was there a positive surgical margin. Mean days to flatus were 2.1, bowel movement 2.8 and discharge home 4.9. There were 41 postoperative complications in 36 patients with 8% having a major complication (Clavien grade 3 or higher) and 11% being readmitted within 30 days of surgery. At a mean followup of 21 months 15 patients had disease recurrence and 6 died of disease. CONCLUSIONS We report a relatively large and maturing experience with robotic radical cystectomy for the treatment of bladder cancer providing acceptable surgical and pathological outcomes. These results support continued efforts to refine the surgical management of high risk bladder cancer.
Cancer Research | 2007
Wolfram Kleeberger; G. Steven Bova; Matthew E. Nielsen; Mehsati Herawi; Ai Ying Chuang; Jonathan I. Epstein; David M. Berman
The intermediate filament protein Nestin identifies stem/progenitor cells in adult tissues, but the function of Nestin is poorly understood. We investigated Nestin expression and function in common lethal cancers. Nestin mRNA was detected in cell lines from small cell lung, and breast cancers, and particularly elevated in cell lines derived from prostate cancer metastases. Whereas the androgen-independent lines PC3, 22RV1, and DU145 all expressed Nestin transcripts under standard culture conditions, the androgen-dependent line LnCaP expressed Nestin only on androgen withdrawal. We confirmed associations of Nestin expression, androgen withdrawal, and metastatic potential by immunohistochemical analysis of samples from 254 prostate cancer patients. Cytoplasmic Nestin protein was readily identifiable in prostate cancer cells from 75% of patients with lethal androgen-independent disease, even in cancer sampled from the prostate itself. However, Nestin expression was undetectable in localized androgen-deprived tumors and in metastases without prior androgen deprivation. To address its function, we reduced Nestin levels with short hairpin RNAs, markedly inhibiting in vitro migration and invasion in prostate cancer cells but leaving cell growth intact. Nestin knockdown also diminished metastases 5-fold compared with controls despite uncompromised tumorigenicity at the site of inoculation. These results specify a function for Nestin in cell motility and identify a novel pathway for prostate cancer metastasis. Activity of this pathway may be selected by the extraprostatic environment or, as supported by our data, may originate within the prostate after androgen deprivation. Further dissection of this novel Nestin migration pathway may lead to strategies to prevent and neutralize metastatic spread.
Journal of Clinical Oncology | 2010
C. Lance Cowey; Chirag Amin; Raj S. Pruthi; Eric Wallen; Matthew E. Nielsen; Gayle Grigson; Cathy Watkins; Keith V. Nance; Jeffrey M. Crane; Mark Jalkut; Dominic T. Moore; William Y. Kim; Paul A. Godley; Young E. Whang; Julia R. Fielding; W.Kimryn Rathmell
PURPOSE The multitargeted tyrosine kinase inhibitor sorafenib is used for the treatment of advanced-stage renal cell carcinoma. However, the safety and efficacy of this agent have yet to be evaluated in the preoperative period, where there may be potential advantages including tumor downstaging. This prospective trial evaluates the safety and feasibility of sorafenib in the preoperative setting. PATIENTS AND METHODS Thirty patients with clinical stage II or higher renal masses, selected based on their candidacy for nephrectomy, underwent preoperative treatment with sorafenib. Toxicities, surgical complications, and tumor responses were monitored. RESULTS Of the thirty patients enrolled, 17 patients had localized disease and 13 had metastatic disease. After a course of sorafenib therapy (median duration, 33 days), a decrease in primary tumor size (median, 9.6%) and radiographic evidence of loss of intratumoral enhancement, quantified using a methodology similar to Choi criteria (median, 13%), was also observed. According to Response Evaluation Criteria in Solid Tumors, of the 28 patients evaluable for response, two patients had a partial response and 26 had stable disease, with no patients progressing on therapy. Toxicities from sorafenib were similar to that expected with this class of medication. All patients were able to proceed with nephrectomy and no surgical complications related to sorafenib administration were observed. CONCLUSION The administration of preoperative sorafenib therapy can impact the size and density of the primary tumor and appears safe and feasible. Further studies are required to determine if preoperative systemic therapy improves outcomes in patients undergoing nephrectomy for renal cell carcinoma.
The Journal of Urology | 2010
Shahrokh F. Shariat; Daher C. Chade; Pierre I. Karakiewicz; Raheela Ashfaq; Hendrik Isbarn; Yves Fradet; Patrick J. Bastian; Matthew E. Nielsen; Umberto Capitanio; Claudio Jeldres; Francesco Montorsi; Seth P. Lerner; Arthur I. Sagalowsky; Richard J. Cote; Yair Lotan
PURPOSE We tested whether the combination of 4 established cell cycle regulators (p53, pRB, p21 and p27) could improve the ability to predict clinical outcomes in a large multi-institutional collaboration of patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder. We also assessed whether the combination of molecular markers is superior to any individual biomarker. MATERIALS AND METHODS The study comprised 692 patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder treated with radical cystectomy and bilateral lymphadenectomy (median followup 5.3 years). Scoring was performed using advanced cell imaging and color detection software. The base model incorporated patient age, gender, stage, grade, lymphovascular invasion, number of lymph nodes removed, number of positive lymph nodes, concomitant carcinoma in situ and adjuvant chemotherapy. RESULTS Individual molecular markers did not improve the predictive accuracy for disease recurrence and cancer specific mortality. Combination of all 4 molecular markers into number of altered molecular markers resulted in significantly higher predictive accuracy than any single biomarker (p <0.001). Moreover addition of number of altered molecular markers to the base model significantly improved the predictive accuracy for disease recurrence (3.9%, p <0.001) and cancer specific mortality (4.3%, p <0.001). Addition of number of altered molecular markers retained statistical significance for improving the prediction of clinical outcomes in the subgroup of patients with pT3N0 (280), pT4N0 (83) and pTany Npositive (329) disease (p <0.001). CONCLUSIONS While the status of individual molecular markers does not add sufficient value to outcome prediction in patients with advanced urothelial carcinoma of the bladder, combinations of molecular markers may improve molecular staging, prognostication and possibly prediction of response to therapy.
Journal of the National Cancer Institute | 2009
Vitaly Margulis; Yair Lotan; Pierre I. Karakiewicz; Yves Fradet; Raheela Ashfaq; Umberto Capitanio; Francesco Montorsi; Patrick J. Bastian; Matthew E. Nielsen; Stefan Müller; J. Rigaud; Lukas C. Heukamp; George J. Netto; Seth P. Lerner; Arthur I. Sagalowsky; Shahrokh F. Shariat
Several small single-center studies have reported a prognostic role for Ki-67 labeling index in advanced urothelial carcinoma of the urinary bladder. To investigate whether Ki-67 was a useful biomarker of oncological outcome after radical cystectomy for urothelial carcinoma, we assessed its expression in tumor tissue from 713 patients treated with radical cystectomy and bilateral lymphadenectomy at six centers. A high Ki-67 labeling index was independently associated with established features of aggressive urothelial carcinoma, disease recurrence, and cancer-specific survival. Addition of Ki-67 labeling index improved the accuracy of standard multivariate outcome prediction models, as measured by Harrell concordance index, by 2.9% for disease recurrence and 2.4% for bladder cancer-specific survival (P < .001, two-sided Mantel-Haenszel) -- a statistically and potentially clinically significant margin. In conclusion, routine assessment of Ki-67 expression status along with assessment of other established predictors of urothelial carcinoma outcome has the potential to improve identification of patients who are at increased risk for disease progression after radical cystectomy and thus may benefit from perioperative systemic chemotherapy.
European Urology | 2010
Raj S. Pruthi; Jeff Nix; Dan McRackan; Adam Hickerson; Matthew E. Nielsen; Matthew Raynor; Eric Wallen
BACKGROUND Recent small case series have now been reported for robotic-assisted laparoscopic radical cystectomy (RALRC). In most of these series, the urinary diversion has been performed in an extracorporeal fashion. There have been few case reports of an intracorporeal diversion and little description of the technique of such a procedure. OBJECTIVE In this paper, we report our initial experience with robotic-assisted laparoscopic intracorporeal urinary diversion, describing stepwise the surgical procedure itself and evaluating perioperative and pathologic outcomes of this novel procedure. DESIGN, SETTING, AND PARTICIPANTS We studied a single-institution case series of patients undergoing robotic-assisted cystectomy and intracorporeal urinary diversion for clinically localized urothelial carcinoma of the bladder (n=10) or for a noncompliant dysfunctional bladder refractory to more conservative management (n=2). Historical comparisons are also made to a consecutive case series of 20 patients undergoing robotic radical cystectomy and extracorporeal urinary diversion. SURGICAL PROCEDURE RALRC and intracorporeal urinary diversion, including ileal conduit (n=9) and orthotopic ileal neobladder (n=3). MEASUREMENTS The stepwise operative procedure is described in detail. Outcome measures evaluated in this series included operative variables, hospital recovery, and complication rate. Comparisons were made to a contemporaneous series of 20 patients who underwent a robotic cystectomy with extracorporeal diversion during this time period (from an experience of >100 robotic cystectomy patients since 2005). RESULTS AND LIMITATIONS Twelve patients (mean age: 60.9 yr) underwent an intracorporeal diversion. Mean operating-room time of all patients was 5.3h, and mean surgical blood loss was 221ml. Mean time to flatus, bowel movement, and hospital discharge was 2.2 d, 3.2 d, and 4.5 d, respectively. Eleven of the 12 patients were discharged on or before postoperative day 5. There were six postoperative complications in five patients (42%), with one complication being Clavien grade 3 or higher. The major limitations of the study are the small sample size and the nonrandomized nature of the compared treatment groups (intracorporeal vs extracorporeal), which limits the ability to directly compare the techniques at a high level of scientific confidence. CONCLUSIONS Our initial experience with robotic-assisted laparoscopic intracorporeal diversion appears to be favorable with acceptable operative and short-term clinical outcomes.
Cancer | 2012
Karyn B. Stitzenberg; Yu Ning Wong; Matthew E. Nielsen; Brian L. Egleston; Robert G. Uzzo
Robotic surgery has been widely adopted for radical prostatectomy. We hypothesized that this change is rapidly shifting procedures away from hospitals that do not offer robotics and consequently increasing patient travel.
The Journal of Urology | 2008
Matthew E. Nielsen; Edward M. Schaeffer; Penny Marschke; Patrick C. Walsh
PURPOSE Recent anatomical studies have shown that branches of the cavernous nerves running adjacent to the prostate at the apex travel more anteriorly than previously recognized. Outcomes of robot assisted radical prostatectomy suggest improved postoperative sexual outcomes following high anterior release of the levator fascia. We prospectively evaluated the effect of high anterior release on oncological and sexual function outcomes following open radical retropubic prostatectomy. MATERIALS AND METHODS A total of 167 patients with clinically localized prostate cancer with a preoperative Sexual Health Inventory for Men score of greater than 21 underwent radical retropubic prostatectomy with bilateral nerve sparing and selective high anterior release, as performed by a single surgeon. Data on postoperative sexual function were collected by an independent third party. Sexual function outcomes at 12 months were defined as 1) a Sexual Health Inventory for Men score of 16 or greater and/or a satisfaction score of 4 or greater and 2) a Sexual Health Inventory for Men score of 22 or greater. RESULTS Because unilateral high anterior release was equivalent to bilateral high anterior release for both definitions (p >0.3), they were combined into 1 group for analyses. Patients undergoing high anterior release were more likely to achieve a Sexual Health Inventory for Men score of 16 or greater and/or a satisfaction score of 4 (93% vs 77%, p = 0.007), and a Sexual Health Inventory for Men score of 22 or greater (70% vs 54%, p = 0.07) at 1 year. Return to baseline (a Sexual Health Inventory for Men score of 22 or greater) was even higher among patients receiving high anterior release who were more sexually active (greater than 1 attempt per week) preoperatively (78% vs 52%, p <0.05). The improved outcomes in potency achieved with high anterior release did not increase the likelihood of a positive surgical margin. CONCLUSIONS Unilateral or bilateral high anterior release of the levator fascia in open radical retropubic prostatectomy provides excellent oncological results and is associated with improved postoperative sexual function.