Faculty Bibliography

BACKGROUND: The surgical robot has been widely adopted in the United States in spite of its high cost and controversy surrounding its benefit. Some have suggested that a "medical arms race" influences technology adoption. We wanted to determine whether a hospital would acquire a surgical robot if its nearest neighboring hospital already owned one. METHODS: We identified 554 hospitals performing radical prostatectomy from the Healthcare Cost and Utilization Project Statewide Inpatient Databases for seven states. We used publicly available data from the website of the surgical robot's sole manufacturer (Intuitive Surgical, Sunnyvale, CA) combined with data collected from the hospitals to ascertain the timing of robot acquisition during year 2001 to 2008. One hundred thirty four hospitals (24%) had acquired a surgical robot by the end of 2008. We geocoded the address of each hospital and determined a hospital's likelihood to acquire a surgical robot based on whether its nearest neighbor owned a surgical robot. We developed a Markov chain method to model the acquisition process spatially and temporally and quantified the "neighborhood effect" on the acquisition of the surgical robot while adjusting simultaneously for known confounders. RESULTS: After adjusting for hospital teaching status, surgical volume, urban status and number of hospital beds, the Markov chain analysis demonstrated that a hospital whose nearest neighbor had acquired a surgical robot had a higher likelihood itself acquiring a surgical robot. (OR=1.71, 95% CI: 1.07-2.72, p=0.02). CONCLUSION: There is a significant spatial and temporal association for hospitals acquiring surgical robots during the study period. Hospitals were more likely to acquire a surgical robot during the robot's early adoption phase if their nearest neighbor had already done so.

BACKGROUND: Cancer continues to rise as a contributor to premature death in the developing world. Despite this, little is known about whether cancer outcomes are related to a country's income level, and what aspects of national healthcare systems are associated with improved cancer outcomes. METHODS: The most recent estimates of cancer incidence and mortality were used to calculate mortality-to-incidence ratio (MIR) for the 85 countries with reliable data. Countries were categorized according to high-income (Gross Domestic Product (GDP)>$15,000) or middle/low-income (GDP<$15,000), and a multivariate linear regression model was used to determine the association between healthcare system indicators and cancer MIR. Indicators study included per capita GDP, overall total healthcare expenditure (THE), THE as a proportion of GDP, total external beam radiotherapy devices (TEBD) per capita, physician density, and the year 2000 WHO healthcare system rankings. RESULTS: Cancer MIR in high-income countries (0.47) was significantly lower than that of middle/low-income countries (0.64), with a p<0.001. In high-income countries, GDP, health expenditure and TEBD showed significant inverse correlations with overall cancer MIR. A $3040 increase in GDP (p=0.004), a $379 increase in THE (p<0.001), or an increase of 0.59 TEBD per 100,000 population (p=0.027) were all associated with a 0.01 decrease in cancer MIR. In middle/low-income countries, only WHO scores correlated with decreased cancer MIR (p=0.022); 12 specific cancer types also showed similar significant correlations (p<0.05) as overall cancer MIR. CONCLUSIONS: The analysis of this study suggested that cancer MIR is greater in middle/low-income countries. Furthermore, the WHO healthcare score was associated with improved cancer outcomes in middle/low-income countries while absolute levels of financial resources and infrastructure played a more important role in high-income countries.

Arsenic (As) exposure has been associated with both urologic malignancy and renal dysfunction; however, its association with hematuria is unknown. We evaluated the association between drinking water As exposure and hematuria in 7843 men enrolled in the Health Effects of Arsenic Longitudinal Study (HEALS). Cross-sectional analysis of baseline data was conducted with As exposure assessed in both well water and urinary As measurements, while hematuria was measured using urine dipstick. Prospective analyses with Cox proportional regression models were based on urinary As and dipstick measurements obtained biannually since baseline up to six years. At baseline, urinary As was significantly related to prevalence of hematuria (P-trend<0.01), with increasing quintiles of exposure corresponding with respective prevalence odds ratios of 1.00 (reference), 1.29 (95% CI: 1.04-1.59), 1.41 (95% CI: 1.15-1.74), 1.46 (95% CI: 1.19-1.79), and 1.56 (95% CI: 1.27-1.91). Compared to those with relatively little absolute urinary As change during follow-up (-10.40 to 41.17mug/l), hazard ratios for hematuria were 0.99 (95% CI: 0.80-1.22) and 0.80 (95% CI: 0.65-0.99) for those whose urinary As decreased by >47.49mug/l and 10.87 to 47.49mug/l since last visit, respectively, and 1.17 (95% CI: 0.94-1.45) and 1.36 (95% CI: 1.10-1.66) for those with between-visit increases of 10.40 to 41.17mug/l and >41.17mug/l, respectively. These data indicate a positive association of As exposure with both prevalence and incidence of dipstick hematuria. This exposure effect appears modifiable by relatively short-term changes in drinking water As.

PURPOSE: The prevalence of lower urinary tract symptoms increases with age and impairs quality of life. Radical prostatectomy has been shown to relieve lower urinary tract symptoms at short-term followup but the long-term effect of radical prostatectomy on lower urinary tract symptoms is unclear. MATERIALS AND METHODS: We performed a prospective cohort study of 1,788 men undergoing radical prostatectomy. The progression of scores from the self-administered AUASS (American Urological Association symptom score) preoperatively, and at 3, 6, 12, 24, 48, 60, 84, 96 and 120 months was analyzed using models controlling for preoperative AUASS, age, prostate specific antigen, pathological Gleason score and stage, nerve sparing, race and marital status. This model was also applied to patients stratified by baseline clinically significant (AUASS greater than 7) and insignificant (AUASS 7 or less) lower urinary tract symptoms. RESULTS: Men exhibited an immediate worsening of lower urinary tract symptoms that improved between 3 months and 2 years after radical prostatectomy. Overall the difference between mean AUASS at baseline and at 10 years was not statistically or clinically significant. Men with baseline clinically significant lower urinary tract symptoms experienced immediate improvements in lower urinary tract symptoms that lasted until 10 years after radical prostatectomy (13.5 vs 8.81, p <0.001). Men with baseline clinically insignificant lower urinary tract symptoms experienced a statistically significant but clinically insignificant increase in mean AUASS after 10 years (3.09 to 4.94, p <0.001). The percentage of men with clinically significant lower urinary tract symptoms decreased from baseline to 10 years after radical prostatectomy (p = 0.02). CONCLUSIONS: Radical prostatectomy is the only treatment for prostate cancer shown to improve and prevent the development of lower urinary tract symptoms at long-term followup. This previously unrecognized long-term benefit argues in favor of the prostate as the primary contributor to male lower urinary tract symptoms.

BACKGROUND: Recent debate about prostate-specific antigen (PSA)-based testing for prostate cancer screening among older men has rarely considered the cost of screening. METHODS: A population-based cohort of male Medicare beneficiaries aged 66 to 99 years, who had never been diagnosed with prostate cancer at the end of 2006 (n = 94,652), was assembled, and they were followed for 3 years to assess the cost of PSA screening and downstream procedures (biopsy, pathologic analysis, and hospitalization due to biopsy complications) at both the national and the hospital referral region (HRR) level. RESULTS: Approximately 51.2% of men received PSA screening tests during the 3-year period, with 2.9% undergoing biopsy. The annual expenditures on prostate cancer screening by the national fee-for-service Medicare program were $447 million in 2009 US dollars. The mean annual screening cost at the HRR level ranged from $17 to $62 per beneficiary. Downstream biopsy-related procedures accounted for 72% of the overall screening costs and varied significantly across regions. Compared with men residing in HRRs that were in the lowest quartile for screening expenditures, men living in the highest HRR quartile were significantly more likely to be diagnosed with prostate cancer of any stage (incidence rate ratio [IRR] = 1.20, 95% confidence interval [CI] = 1.07-1.35) and localized cancer (IRR = 1.30, 95% CI = 1.15-1.47). The IRR for regional/metastasized cancer was also elevated, although not statistically significant (IRR = 1.31, 95% CI = 0.81-2.11). CONCLUSIONS: Medicare prostate cancer screening-related expenditures are substantial, vary considerably across regions, and are positively associated with rates of cancer diagnosis. Cancer 2014;120:96-102. (c) 2013 American Cancer Society.

Large cell neuroendocrine carcinoma of the prostate (LCNEC), de novo in particular, is an extremely rare entity that has only been described in the literature in case reports. Historically, the majority of the cases of LCNEC reported in the literature represent typical prostatic adenocarcinomas that transformed after long standing androgen deprivation therapy (ADT). These cases were admixed with histological areas of usual adenocarcinoma and showed hybrid features of both neuroendocrine and usual adenocarcinoma. Here we present a case of an LCNEC without admixed areas of usual prostatic adenocarcinoma arising de novo in a patient without prior history of hormonal therapy. The tumor also shows morphologic evidence of neuroendocrine differentiation; composed of large sheets and nests of cells with moderate amphophilic cytoplasm with peripheral palisading, and vesicular clumpy chromatin with prominent nucleoli. The carcinoma's prostatic origin is indicated by positive immunohistochemical staining for PSA, PAP, PSMA, racemase, and Nkx3.1. Diffusely positive staining for chromogranin and synaptophysin, as well as the presence of secretory granules in the cytoplasm of the tumor cells demonstrated by electron microscopy supports the NE differentiation. NE prostate cancer usually does not express AR and is refractory to ADT therapy while AR and ERG are positive in this case. In summary, we report a de novo LCNEC of the prostate with review of literature, in particular, clinical implications.

OBJECTIVE: To assess the impact of the American Urological Association (AUA) guidelines advocating partial nephrectomy for T1 tumors guidelines on the likelihood of undergoing partial nephrectomy. MATERIALS AND METHODS: We analyzed the Nationwide Inpatient Sample (NIS), a dataset encompassing 20% of all United States inpatient hospitalizations, from 2007 through 2010. Our dependent variable was receipt of radical vs partial nephrectomy (55.50, 55.51, 55.52, and 55.54 vs 55.4) for a renal mass (International Classification of Disease, 9th Revision [ICD-9] code 189.0). The independent variable of interest was time of surgery (before or after the establishment of AUA guidelines); covariates included a diagnosis of chronic kidney disease (CKD), overall comorbidity, age, race, gender, geographic region, income, and hospital characteristics. Bivariate and multivariable adjusted logistic regression was used to determine the association between receipt of partial nephrectomy and time of guideline establishment. RESULTS: We identified 26,165 patients with renal tumors who underwent surgery. Before the guidelines, 4031 patients (27%) underwent partial nephrectomy compared to 3559 (32%) after. On multivariable analysis, undergoing surgery after the establishment of guidelines (odds ratio [OR] 1.20, 95% confidence interval [CI] 1.08-1.32, P <.01) was an independent predictor of partial nephrectomy. Other factors associated with partial nephrectomy were urban location, surgery at a teaching hospital, large hospital bed size, Northeast location, and Black race. Female gender and CKD were not associated with partial nephrectomy. CONCLUSION: Although adoption of partial nephrectomy increased after establishment of new guidelines on renal masses, partial nephrectomy remains an underutilized procedure. Future research must focus on barriers to adoption of partial nephrectomy and how to overcome them.

BACKGROUND: Reducing inappropriate use of imaging to stage incident prostate cancer is a challenging problem highlighted recently as a Physician Quality Reporting System quality measure and by the American Society of Clinical Oncology and the American Urological Association in the Choosing Wisely campaign. Since 2000, the National Prostate Cancer Register (NPCR) of Sweden has led an effort to decrease national rates of inappropriate prostate cancer imaging by disseminating utilization data along with the latest imaging guidelines to urologists in Sweden. We sought to determine the temporal and regional effects of this effort on prostate cancer imaging rates. METHODS: We performed a retrospective cohort study among men diagnosed with prostate cancer from the NPCR from 1998 to 2009 (n = 99 879). We analyzed imaging use over time stratified by clinical risk category (low, intermediate, high) and geographic region. Generalized linear models with a logit link were used to test for time trend. RESULTS: Thirty-six percent of men underwent imaging within 6 months of prostate cancer diagnosis. Overall, imaging use decreased over time, particularly in the low-risk category, among whom the imaging rate decreased from 45% to 3% (P < .001), but also in the high-risk category, among whom the rate decreased from 63% to 47% (P < .001). Despite substantial regional variation, all regions experienced clinically and statistically (P < .001) significant decreases in prostate cancer imaging. CONCLUSIONS: A Swedish effort to provide data on prostate cancer imaging use and imaging guidelines to clinicians was associated with a reduction in inappropriate imaging over a 10-year period, as well as slightly decreased appropriate imaging in high-risk patients. These results may inform current efforts to promote guideline-concordant imaging in the United States and internationally.

Whether clinical cancer research currently focuses on gaps in the evidentiary basis for clinical guidelines and/or on cancers that impose greater societal burden is unclear. This study assessed the relationship between cancer research efforts in terms of planned randomized controlled trial (RCT) enrollment, objective measures of evidence quality, and a cancer's burden on society. The authors calculated the planned RCT enrollment listed on ClinicalTrials.gov for the 17 most prevalent solid cancers. Using cancer type as the unit of analysis, linear regression was used to examine the association between planned enrollment in RCTs and 1) evidence quality, as measured by the absolute number and percent of highest quality category (category 1 [C1]) recommendations in the NCCN Clinical Practice Guidelines in Oncology for each cancer, and 2) measures of burden on society, including prevalence, incidence, person-years of life lost (PYLL), and disability-adjusted life years (DALY). Non-normal distributions were log transformed when appropriate. Overall, 15% of the NCCN recommendations were based on the highest quality evidence. Results produced 1260 RCTs. Planned RCT enrollment ranged from 2270 (testis) to 492,876 (breast) and was correlated neither with absolute number nor percent of C1 recommendations for that cancer. Planned RCT enrollment was positively correlated with a cancer's prevalence (P=.01), incidence (P<.01), PYLL (P<.01), and DALY (P<0.01). In multivariate analysis, prevalence (P<.01) and PYLL (P<.01) had the strongest association with planned RCT enrollment. Findings showed, therefore, that planned cancer RCT enrollment is associated with higher societal disease burden, not the quality of a cancer's clinical guidelines.