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Dive into the research topics where Brent K. Hollenbeck is active.

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Featured researches published by Brent K. Hollenbeck.


The Lancet | 2006

Medical therapy to facilitate urinary stone passage: a meta-analysis

John M. Hollingsworth; Mary A.M. Rogers; Samuel R. Kaufman; Timothy J Bradford; Sanjay Saint; John T. Wei; Brent K. Hollenbeck

BACKGROUND Medical therapies to ease urinary-stone passage have been reported, but are not generally used. If effective, such therapies would increase the options for treatment of urinary stones. To assess efficacy, we sought to identify and summarise all randomised controlled trials in which calcium-channel blockers or alpha blockers were used to treat urinary stone disease. METHODS We searched MEDLINE, Pre-MEDLINE, CINAHL, and EMBASE, as well as scientific meeting abstracts, up to July, 2005. All randomised controlled trials in which calcium-channel blockers or alpha blockers were used to treat ureteral stones were eligible for inclusion in our analysis. Data from nine trials (number of patients=693) were pooled. The main outcome was the proportion of patients who passed stones. We calculated the summary estimate of effect associated with medical therapy use using random-effects and fixed-effects models. FINDINGS Patients given calcium-channel blockers or alpha blockers had a 65% (absolute risk reduction=0.31 95% CI 0.25-0.38) greater likelihood of stone passage than those not given such treatment (pooled risk ratio 1.65; 95% CI 1.45-1.88). The pooled risk ratio for alpha blockers was 1.54 (1.29-1.85) and for calcium-channel blockers with steroids was 1.90 (1.51-2.40). The proportion of heterogeneity not explained by chance alone was 28%. The number needed to treat was 4. INTERPRETATION Although a high-quality randomised trial is necessary to confirm its efficacy, our findings suggest that medical therapy is an option for facilitation of urinary-stone passage for patients amenable to conservative management, potentially obviating the need for surgery.


The Journal of Urology | 2006

Partial Nephrectomy for Small Renal Masses: An Emerging Quality of Care Concern?

David C. Miller; John M. Hollingsworth; Khaled S. Hafez; Stephanie Daignault; Brent K. Hollenbeck

PURPOSE The recent popularization of laparoscopic radical nephrectomy may beget underuse of partial nephrectomy. To evaluate this concern we used the SEER registry to characterize national practice patterns for the surgical management of small renal masses. MATERIALS AND METHODS Between 1988 and 2001, 14,647 patients with primary tumor size 7 cm or less were treated surgically for locoregional kidney cancer. The proportion of patients treated with PN was determined and stratified by year of diagnosis and tumor size. Multivariate models were developed to identify independent determinants of PN use and overall survival following surgical treatment of kidney cancer. RESULTS Overall 1,401 patients (9.6%) were treated with PN vs 13,246 (90.4%) who underwent total nephrectomy. For tumors 7 cm or less, the use of PN increased progressively between 1988 (4.6%) and 2001 (17.6%, p < 0.001). Despite this trend PN remained fairly uncommon even for the smallest renal masses. Among patients with tumors less than 2 cm, 14% underwent PN in 1988 to 1989 vs 42% in 2000 to 2001. For tumors 2 to 4 cm the corresponding proportions were 5% and 20%, respectively (p < 0.001). Younger patient age, smaller tumor size and more recent diagnostic year were independent determinants of PN use (all p values < 0.05). All cause mortality was similar for patients treated with PN vs TN (HR 0.9, 95% CI 0.8-1.1). CONCLUSIONS Despite more frequent application during the last 2 decades, nationwide use of PN remains relatively uncommon, even for the smallest renal masses. Recognizing the favorable outcomes associated with preservation of renal parenchyma, our findings identify a possible quality of care concern that should be addressed by the urological community.


Science Translational Medicine | 2011

Urine TMPRSS2:ERG Fusion Transcript Stratifies Prostate Cancer Risk in Men with Elevated Serum PSA

Scott A. Tomlins; Sheila M.J. Aubin; Javed Siddiqui; Robert J. Lonigro; Laurie Sefton-Miller; Siobhan Miick; Sarah Williamsen; Petrea Hodge; Jessica Meinke; Amy Blase; Yvonne Penabella; John R. Day; Radhika Varambally; Bo Han; David P. Wood; Lei Wang; Martin G. Sanda; Mark A. Rubin; Daniel R. Rhodes; Brent K. Hollenbeck; Kyoko Sakamoto; Jonathan L. Silberstein; Yves Fradet; James B. Amberson; Stephanie Meyers; Nallasivam Palanisamy; Harry G. Rittenhouse; John T. Wei; Jack Groskopf; Arul M. Chinnaiyan

Urine TMPRSS2:ERG gene fusion could be used for stratification of patients at higher risk for prostate cancer. Old Gene Fusion, New Diagnostic Tricks The “PSA test” is a routine test for men over the age of 50 or for those at risk for prostate cancer. It measures the level of prostate-specific antigen (PSA) in the blood, and if that level is above a predefined cutoff, a biopsy is recommended for definitive diagnosis. This test is not perfect; benign conditions, such as an enlarged prostate, can contribute to high levels of PSA, resulting in a “false-positive” and subsequent overdiagnosis and overtreatment. Because of the high prevalence of prostate cancer (it is estimated that nearly 250,000 men will be diagnosed with the disease in 2011), it is clear that a more accurate test for prostate cancer is needed. Here, Tomlins et al. improve on the PSA test by taking a new twist on a known gene fusion, using it to stratify more than 1000 men in two multicenter cohorts based on risk for developing the disease. Recently, it was discovered that the fusion of two genes, the transmembrane protease, serine 2 (TMPRSS2) gene and the v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG) gene, known as TMPRSS2:ERG, is overexpressed in more than 50% of PSA-screened prostate cancers. The protein product of this fusion cannot be detected in serum, so the authors decided to test for the presence of TMPRSS2:ERG mRNA in urine. First, they developed a clinical-grade, transcription-mediated amplification assay for quantifying fusion mRNA—this generated a TMPRSS2:ERG “score.” Urine TMPRSS2:ERG score was linked to the presence of cancer, tumor volume, and clinically significant cancer in patients. Then, the authors combined the TMPRSS2:ERG score with the level of prostate cancer antigen 3 (PCA3) in urine. TMPRSS2:ERG+PCA3 improved the performance of the multivariate Prostate Cancer Prevention Trial risk calculator, thus demonstrating clinical utility. Who said you can’t teach an old gene fusion new tricks? By combining the cancer-specific fusion TMPRSS2:ERG score with levels of PSA (in serum) and PCA3 (in urine), Tomlins and colleagues demonstrated more accurate, individualized stratification of men at high risk for developing clinically significant prostate cancer—an important step in streamlining diagnosis and treatment. Moreover, men with extremes of TMPRSS2:ERG+PCA3 had different risks of cancer on biopsy; in combination with other clinicopathological features, urine TMPRSS2:ERG+PCA3 might also inform the urgency of biopsy after PSA screening. More than 1,000,000 men undergo prostate biopsy each year in the United States, most for “elevated” serum prostate-specific antigen (PSA). Given the lack of specificity and unclear mortality benefit of PSA testing, methods to individualize management of elevated PSA are needed. Greater than 50% of PSA-screened prostate cancers harbor fusions between the transmembrane protease, serine 2 (TMPRSS2) and v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG) genes. Here, we report a clinical-grade, transcription-mediated amplification assay to risk stratify and detect prostate cancer noninvasively in urine. The TMPRSS2:ERG fusion transcript was quantitatively measured in prospectively collected whole urine from 1312 men at multiple centers. Urine TMPRSS2:ERG was associated with indicators of clinically significant cancer at biopsy and prostatectomy, including tumor size, high Gleason score at prostatectomy, and upgrading of Gleason grade at prostatectomy. TMPRSS2:ERG, in combination with urine prostate cancer antigen 3 (PCA3), improved the performance of the multivariate Prostate Cancer Prevention Trial risk calculator in predicting cancer on biopsy. In the biopsy cohorts, men in the highest and lowest of three TMPRSS2:ERG+PCA3 score groups had markedly different rates of cancer, clinically significant cancer by Epstein criteria, and high-grade cancer on biopsy. Our results demonstrate that urine TMPRSS2:ERG, in combination with urine PCA3, enhances the utility of serum PSA for predicting prostate cancer risk and clinically relevant cancer on biopsy.


The Journal of Urology | 2001

COMPLICATIONS OF URETEROSCOPY: ANALYSIS OF PREDICTIVE FACTORS

Timothy G. Schuster; Brent K. Hollenbeck; Gary J. Faerber; J. Stuart Wolf

PURPOSE Although overall and major complication rates of 10% to 20% and 0% to 6%, respectively, have been observed in large series of ureteroscopy, to our knowledge no systemic analysis to determine factors predictive of these complications has been reported. MATERIALS AND METHODS We retrospectively reviewed all ureteroscopies performed at our institution for calculous disease from January 1997 through September 1999. A total of 322 procedures were performed by 5 attending surgeons. Intraoperative and immediate postoperative complications were identified. Bivariate and multivariate analysis was performed to identify associated factors with ureteral perforation and postoperative complications as the dependent variables. RESULTS Bivariate analysis showed a significant association of ureteral perforation with increased operative time (p = 0.0001). In addition, we noted a significant association of postoperative complications with stones in the kidney (p = 0.0004), operative time (p = 0.05) and decreased surgeon experience (p = 0.0035) as well as a trend toward significance for the type of ureteroscope used (p = 0.0609). In multivariate logistic regression models ureteral perforation remained highly associated with operative time (p = 0.0005) when controlling for the other factors. Similarly decreased surgeon experience and a stone in the kidney were predictive of postoperative complications when controlling for the other factors (p = 0.004). CONCLUSIONS Longer duration of the ureteroscopic procedure is strongly associated with ureteral perforation. The likelihood of immediate postoperative complications is greater when renal calculi are treated and less when the surgeon is more experienced.


Cancer | 2007

Five-year survival after surgical treatment for kidney cancer: a population-based competing risk analysis.

John M. Hollingsworth; David C. Miller; Stephanie Daignault; Brent K. Hollenbeck

Kidney cancers rising incidence is largely attributable to the increased detection of small renal masses. Although surgery rates have paralleled this incidence trend, mortality continues to rise, calling into question the necessity of surgery for all patients with renal masses. Using a population‐based cohort, a competing risk analysis was performed to estimate patient survival after surgery for kidney cancer, as a function of patient age and tumor size at diagnosis.


Journal of Clinical Oncology | 2006

Volume-Based Referral for Cancer Surgery: Informing the Debate

Brent K. Hollenbeck; Rodney L. Dunn; David C. Miller; Stephanie Daignault; David A. Taub; John T. Wei

PURPOSE Mounting evidence suggests a relationship between hospital volume and outcomes after major cancer surgery; however, the absolute benefits of volume-based referral on a national basis are unclear. PATIENTS AND METHODS Data from the Nationwide Inpatient Sample were used to measure the likelihood of operative mortality and a prolonged length of stay (LOS) after six cancer surgeries (prostatectomy, cystectomy, esophagectomy, pancreatectomy, pneumonectomy, and liver resection) between 1993 and 2003. Using sampling weights, the adjusted likelihood of the outcomes was used to calculate the number of lives saved (or prolonged LOS avoided) in the United States. RESULTS The magnitude of the volume-operative mortality effect varied from an adjusted odds ratio (OR) of 1.3 (95% CI, 0.8 to 2.3) for cystectomy to 4.9 (95% CI, 2.4 to 10.1) for pancreatectomy. After accounting for varying rates of procedure utilization, the lives saved per 100 surgeries regionalized ranged from 0.2 (95% CI, 0.12 to 0.24 lives saved) for prostatectomy to 9.2 (95% CI, 6.7 to 10.4 lives saved) for pancreatectomy. The volume-prolonged LOS effect varied from an adjusted OR of 0.9 (95% CI, 0.5 to 1.6) for liver resection to 4.8 (95% CI, 3.5 to 6.7) for prostatectomy. After accounting for procedure use, the number of prolonged hospitalizations avoided ranged from -1.7 (95% CI, -11.3 to 3.6 hospitalizations) to 14.3 (95% CI, 12.9 to 15.4 hospitalizations) per 100 surgeries regionalized for liver resection and prostatectomy, respectively. CONCLUSION For patients undergoing major cancer surgery, the benefits of volume-based referral depend on the interplay between procedure utilization, the magnitude of effect, and the outcome chosen.


European Urology | 2013

A systematic review of the volume-outcome relationship for radical prostatectomy

Quoc-Dien Trinh; Anders Bjartell; Stephen J. Freedland; Brent K. Hollenbeck; Jim C. Hu; Shahrokh F. Shariat; Maxine Sun; Andrew J. Vickers

CONTEXT Due to the complexity and challenging nature of radical prostatectomy (RP), it is likely that both short- and long-term outcomes strongly depend on the cumulative number of cases performed by the surgeon as well as by the hospital. OBJECTIVE To review systematically the association between hospital and surgeon volume and perioperative, oncologic, and functional outcomes after RP. EVIDENCE ACQUISITION A systematic review of the literature was performed, searching PubMed, Embase, and Scopus databases for original and review articles between January 1, 1995, and December 31, 2011. Inclusion and exclusion criteria comprised RP, hospital and/or surgeon volume reported as a predictor variable, a measurable end point, and a description of multiple hospitals or surgeons. EVIDENCE SYNTHESIS Overall 45 publications fulfilled the inclusion criteria, where most data originated from retrospective institutional or population-based cohorts. Studies generally focused on hospital or surgeon volume separately. Although most of these analyses corroborated the impact of increasing volume with better outcomes, some failed to find any significant effect. Studies also differed with respect to the proposed volume cut-off for improved outcomes, as well as the statistical means of evaluating the volume-outcome relationship. Five studies simultaneously compared hospital and surgeon volume, where results suggest that the importance of either hospital or surgeon volume largely depends on the end point of interest. CONCLUSIONS Undeniable evidence suggests that increasing volume improves outcomes. Although it would seem reasonable to refer RP patients to high-volume centers, such regionalization may not be entirely practical. As such, the implications of such a shift in practice have yet to be fully determined and warrant further exploration.


European Urology | 2014

Analysis of intracorporeal compared with extracorporeal urinary diversion after robot-assisted radical cystectomy: Results from the international robotic cystectomy consortium

Kamran Ahmed; Shahid Khan; Matthew H. Hayn; Piyush K. Agarwal; Ketan K. Badani; M. Derya Balbay; Erik P. Castle; Prokar Dasgupta; Reza Ghavamian; Khurshid A. Guru; Ashok K. Hemal; Brent K. Hollenbeck; Adam S. Kibel; Mani Menon; Alex Mottrie; Kenneth G. Nepple; John Pattaras; James O. Peabody; Vassilis Poulakis; Raj S. Pruthi; Joan Palou Redorta; Koon Ho Rha; Lee Richstone; Matthias Saar; Douglas S. Scherr; S. Siemer; Michael Stoeckle; Eric Wallen; Alon Z. Weizer; Peter Wiklund

BACKGROUND Intracorporeal urinary diversion (ICUD) has the potential benefits of a smaller incision, reduced pain, decreased bowel exposure, and reduced risk of fluid imbalance. OBJECTIVE To compare the perioperative outcomes of patients undergoing extracorporeal urinary diversion (ECUD) and ICUD following robot-assisted radical cystectomy (RARC). DESIGN, SETTING, AND PARTICIPANTS We reviewed the database of the International Robotic Cystectomy Consortium (IRCC) (18 international centers), with 935 patients who had undergone RARC and pelvic lymph node dissection (PLND) between 2003 and 2011. INTERVENTION All patients within the IRCC underwent RARC and PLND as indicated. The urinary diversion was performed either intracorporeally or extracorporeally. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Demographic data, perioperative outcomes, and complications in patients undergoing ICUD or ECUD were compared. All patients had at least a 90-d follow-up. The Fisher exact test was used to summarize categorical variables and the Wilcoxon rank sum test or Kruskal-Wallis test for continuous variables. RESULTS AND LIMITATIONS Of 935 patients who had RARC and PLND, 167 patients underwent ICUD (ileal conduit: 106; neobladder: 61), and 768 patients had an ECUD (ileal conduit: 570; neobladder: 198). Postoperative complications data were available for 817 patients, with a minimum follow-up of 90 d. There was no difference in age, gender, body mass index, American Society of Anesthesiologists grade, or rate of prior abdominal surgery between the groups. The operative time was equivalent (414 min), with the median hospital stay being marginally longer for the ICUD group (9 d vs 8 d, p=0.086). No difference in the reoperation rates at 30 d was noted between the groups. The 90-d complication rate was not significant between the two groups, but a trend favoring ICUD over ECUD was noted (41% vs 49%, p=0.05). Gastrointestinal complications were significantly lower in the ICUD group (p ≤ 0.001). Patients with ICUD were at a lower risk of experiencing a postoperative complication at 90 d (32%) (odds ratio: 0.68; 95% confidence interval, 0.50-0.94; p=0.02). Being a retrospective study was the main limitation. CONCLUSIONS Robot-assisted ICUD can be accomplished safely, with comparable outcomes to open urinary diversion. In this cohort, patients undergoing ICUD had a relatively lower risk of complications.


JAMA | 2013

Use of Advanced Treatment Technologies Among Men at Low Risk of Dying From Prostate Cancer

Bruce L. Jacobs; Yun Zhang; Florian R. Schroeck; Ted A. Skolarus; John T. Wei; James E. Montie; Scott M. Gilbert; Seth A. Strope; Rodney L. Dunn; David C. Miller; Brent K. Hollenbeck

IMPORTANCE The use of advanced treatment technologies (ie, intensity-modulated radiotherapy [IMRT] and robotic prostatectomy) for prostate cancer is increasing. The extent to which these advanced treatment technologies have disseminated among patients at low risk of dying from prostate cancer is uncertain. OBJECTIVE To assess the use of advanced treatment technologies, compared with prior standards (ie, traditional external beam radiation treatment [EBRT] and open radical prostatectomy) and observation, among men with a low risk of dying from prostate cancer. DESIGN, SETTING, AND PATIENTS Using Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we identified a retrospective cohort of men diagnosed with prostate cancer between 2004 and 2009 who underwent IMRT (n = 23,633), EBRT (n = 3926), robotic prostatectomy (n = 5881), open radical prostatectomy (n = 6123), or observation (n = 16,384). Follow-up data were available through December 31, 2010. MAIN OUTCOMES AND MEASURES The use of advanced treatment technologies among men unlikely to die from prostate cancer, as assessed by low-risk disease (clinical stage ≤T2a, biopsy Gleason score ≤6, and prostate-specific antigen level ≤10 ng/mL), high risk of noncancer mortality (based on the predicted probability of death within 10 years in the absence of a cancer diagnosis), or both. RESULTS In our cohort, the use of advanced treatment technologies increased from 32% (95% CI, 30%-33%) to 44% (95% CI, 43%-46%) among men with low-risk disease (P < .001) and from 36% (95% CI, 35%-38%) to 57% (95% CI, 55%-59%) among men with high risk of noncancer mortality (P < .001). The use of these advanced treatment technologies among men with both low-risk disease and high risk of noncancer mortality increased from 25% (95% CI, 23%-28%) to 34% (95% CI, 31%-37%) (P < .001). Among all patients diagnosed in SEER, the use of advanced treatment technologies for men unlikely to die from prostate cancer increased from 13% (95% CI, 12%-14%), or 129.2 per 1000 patients diagnosed with prostate cancer, to 24% (95% CI, 24%-25%), or 244.2 per 1000 patients diagnosed with prostate cancer (P < .001). CONCLUSION AND RELEVANCE Among men diagnosed with prostate cancer between 2004 and 2009 who had low-risk disease, high risk of noncancer mortality, or both, the use of advanced treatment technologies has increased.


Urology | 2002

Processed total motile sperm count correlates with pregnancy outcome after intrauterine insemination

David C. Miller; Brent K. Hollenbeck; Gary D. Smith; John F. Randolph; Gregory M. Christman; Yolanda R. Smith; Dan I. Lebovic; Dana A. Ohl

OBJECTIVES To determine the impact of processed total motile sperm (PTMS) count on pregnancy after partner intrauterine insemination (IUI). IUI is generally attempted before proceeding to more expensive and invasive assisted-reproductive techniques such as intracytoplasmic sperm injection. Several semen parameters have been shown to correlate with IUI outcome and may be useful when counseling couples. METHODS Four hundred thirty-eight couples with diverse causes of infertility underwent 1114 cycles of husband IUI during a 39-month period. The clinical and semen parameters were recorded for each couple and each insemination. The parameters were compared between those couples who achieved a pregnancy and those who did not. RESULTS The total number of pregnancies was 120, resulting in a pregnancy rate per cycle of 10.8% and a couple pregnancy rate of 27.4%. On multivariable logistic regression analysis, the PTMS count was independently associated with fertility after IUI (P = 0.0014). Moreover, the pregnancy rate was significantly lower for couples with less than 10 million PTMS (P <0.05). CONCLUSIONS The results of this study have demonstrated that the PTMS count independently predicts success with IUI. Cycles with less than 10 million total motile sperm are significantly less likely to result in a pregnancy. If cause-specific therapy has failed, alternatives to IUI should be considered for couples when the PTMS count is less than 10 million.

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John T. Wei

University of Michigan

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