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Featured researches published by Ganesh Sivarajan.


The Journal of Urology | 2013

Positive Surgical Margins in Robot-Assisted Partial Nephrectomy: A Multi-Institutional Analysis of Oncologic Outcomes (Leave No Tumor Behind)

Ali Khalifeh; Jihad H. Kaouk; Sam B. Bhayani; Craig G. Rogers; Michael D. Stifelman; Youssef S. Tanagho; Ramesh Kumar; Michael A. Gorin; Ganesh Sivarajan; Dinesh Samarasekera; Mohamad E. Allaf

PURPOSE Expanding indications for robot-assisted partial nephrectomy raise major oncologic concerns for positive surgical margins. Previous reports showed no correlation between positive surgical margins and oncologic outcomes. We report a multi-institutional experience with the oncologic outcomes of positive surgical margins on robot-assisted partial nephrectomy. MATERIALS AND METHODS Pathological and clinical followup data were reviewed from an institutional review board approved, prospectively maintained joint database from 5 institutions. Tumors with malignant pathology were isolated and statistically analyzed for demographics and oncologic followup. The log rank test was used to compare recurrence-free and metastasis-free survival between patients with positive and negative surgical margins. The proportional hazards method was used to assess the influence of multiple factors, including positive surgical margins, on recurrence and metastasis. RESULTS A total of 943 robot-assisted partial nephrectomies for malignant tumors were successfully completed. Of the patients 21 (2.2%) had positive surgical margins on final pathological assessment, resulting in 2 groups, including the 21 with positive surgical margins and 922 with negative surgical margins. Positive surgical margin cases had higher recurrence and metastasis rates (p<0.001). As projected by the Kaplan-Meier method in the population as a whole at followup out to 63.6 months, 5-year recurrence-free and metastasis-free survival was 94.8% and 97.5%, respectively. There was a statistically significant difference in recurrence-free and metastasis-free survival between patients with positive and negative surgical margins (log rank test<0.001), which favored negative surgical margins. Positive surgical margins showed an 18.4-fold higher HR for recurrence when adjusted for multiple tumors, tumor size, tumor growth pattern and pathological stage. CONCLUSIONS Positive surgical margins on final pathological evaluation increase the HR of recurrence and metastasis. In addition to pathological and molecular tumor characteristics, this should be considered to plan appropriate management.


European Urology | 2014

Ten-year Outcomes of Sexual Function After Radical Prostatectomy: Results of a Prospective Longitudinal Study

Ganesh Sivarajan; Vinay Prabhu; Glen B. Taksler; Juliana Laze; Herbert Lepor

BACKGROUND The long-term impact of radical prostatectomy (RP) on sexual function (SF) and erectile function (EF) has important implications related to the risk-to-benefit ratio of this treatment. OBJECTIVE To determine the long-term effect of RP on male SF and EF over 10 yr of follow-up. DESIGN, SETTING, AND PARTICIPANTS This was a prospective, longitudinal outcomes study in 1836 men following RP at a university hospital. Men were invited to complete the University of California, Los Angeles, Prostate Cancer Index SF survey at baseline, 3, 6, 12, 24, 96, and 120 mo postoperatively and a survey at 4 and 7 yr postoperatively assessing global changes in their EF over the preceding 2 yr. INTERVENTION All men underwent open RP. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Multiple, generalized linear regression models were used to evaluate the association between time following RP and SF and EF scores controlling for age, prostate-specific antigen, Gleason scores, stage, nerve sparing, race, and marital status. RESULTS AND LIMITATIONS After an expected initial decline, time-dependent improvements in SF and EF were observed through 2 yr postoperatively. Overall, SF and EF were both generally stable between 2 and 10 yr following RP. The subgroups of younger men and men with better preoperative function were more likely to maintain their EF and SF through 10 yr following RP. The primary limitation is the potential bias attributable to nonresponders. CONCLUSIONS The recovery of EF can extend well beyond 2 yr. There is a significant association between younger age and better preoperative function and the likelihood of experiencing improvements beyond 2 yr. Assessing the comparative effectiveness of treatment options for localized prostate cancer must examine SF beyond 2 yr to account for delayed treatment effects and the natural history of SF in the aging male population.


The Journal of Urology | 2013

Outcomes and predictors of clinical T1 to pathological T3a tumor up-staging after robotic partial nephrectomy: a multi-institutional analysis.

Michael A. Gorin; Mark W. Ball; Phillip M. Pierorazio; Youssef S. Tanagho; Sam B. Bhayani; Jihad H. Kaouk; Craig G. Rogers; Michael D. Stifelman; Ali Khalifeh; Ramesh Kumar; Ganesh Sivarajan; Mohamad E. Allaf

PURPOSE We evaluated the early oncological end point of recurrence-free survival in patients with renal cell carcinoma up-staged from cT1 to pT3a after partial nephrectomy. We also aimed to establish preoperative factors associated with pathological tumor up-staging. MATERIALS AND METHODS A prospective database of robotic partial nephrectomy cases performed at 5 academic centers was queried for patients who underwent surgery for a solitary cT1 renal mass. Patients with pT1-2 renal cell carcinoma were compared to those with pT3a tumors to determine the difference in recurrence-free survival. Preoperative factors associated with cT1 to pT3a up-staging were studied using multivariate logistic regression analysis. RESULTS A total of 1,096 patients underwent robotic partial nephrectomy for a cT1 renal mass. At final pathological evaluation 855 tumors (78.0%) were found to be renal cell carcinoma, of which 41 (4.8%) were up-staged to pT3a. The 24-month recurrence-free survival estimates for pT1-2 and pT3a tumors were 99.2% and 91.8%, respectively (p=0.003). Multivariate analysis revealed that a high vs low R.E.N.A.L. (radius, exophytic/endophytic, nearness to collecting system or sinus, anterior/posterior and location relative to polar lines) nephrometry score was associated with tumor up-staging (OR 2.97, 95% CI 1.20-7.35, p=0.02). On separate multivariate analysis increasing tumor diameter (OR 1.66, 95% CI 1.32-2.08, p<0.001) and hilar location (OR 2.83, 95% CI 1.43-5.61, p=0.003) were also associated with up-staging. CONCLUSIONS At short-term followup patients with renal cell carcinoma up-staged from cT1 to pT3a have reasonable oncological outcomes after partial nephrectomy. Factors associated with tumor up-staging include high tumor complexity, increasing tumor diameter and hilar location. Further studies are needed to determine the comparative efficacy of partial vs radical nephrectomy for small pT3a tumors.


European Urology | 2014

Long-term continence outcomes in men undergoing radical prostatectomy for clinically localized prostate cancer

Vinay Prabhu; Ganesh Sivarajan; Glen B. Taksler; Juliana Laze; Herbert Lepor

BACKGROUND Urinary incontinence is a common short-term complication of radical prostatectomy (RP). Little is known about the long-term impact of RP on continence. OBJECTIVE To elucidate the long-term progression of continence after RP. DESIGN, SETTING, AND PARTICIPANTS From October 2000 through September 2012, 1788 men undergoing open RP for clinically localized prostate cancer by a single surgeon at an urban tertiary care center prospectively signed consent to be followed before RP and at 3, 6, 12, 24, 96, and 120 mo after RP. A consecutive sampling method was used and all men were included in this study. INTERVENTION Men underwent open RP. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Regression models controlled for preoperative University of California, Los Angeles-Prostate Cancer Index urinary function score (UCLA-PCI-UFS), age, prostate-specific antigen level, Gleason score, stage, nerve-sparing status, race, and marital status were used to evaluate the association of time since RP with two dependent variables: UCLA-PCI-UFS and continence status. RESULTS AND LIMITATION The mean UCLA-PCI-UFS declined between 2 yr and 8 yr (83.8 vs 81.8; p=0.007) and marginally between 8 yr and 10 yr (81.8 vs 79.6; p=0.036) after RP, whereas continence rate did not significantly change during these intervals. Men ≥ 60 yr old experienced a decline in mean UCLA-PCI-UFS between 2 yr and 8 yr (p=0.002) and a marginal decline in continence rate between 2 yr and 10 yr (p=0.047), whereas these variables did not change significantly in men <60 yr old. These outcomes are for an experienced surgeon, so caution should be exercised in generalizing these results. CONCLUSIONS Between 2 yr and 10 yr after RP, there were slight decreases in mean UCLA-PCI-UFS and continence rates in this study. Men aged <60 yr had better long-term outcomes. These results provide realistic long-term continence expectations for men undergoing RP.


Urology | 2013

National Trends in the Utilization of Partial Nephrectomy Before and After the Establishment of AUA Guidelines for the Management of Renal Masses

Marc A. Bjurlin; Dawn Walter; Glen B. Taksler; William C. Huang; James S. Wysock; Ganesh Sivarajan; Stacy Loeb; Samir S. Taneja; Danil V. Makarov

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.


The Journal of Urology | 2014

Radical Prostatectomy Improves and Prevents Age Dependent Progression of Lower Urinary Tract Symptoms

Vinay Prabhu; Glen B. Taksler; Ganesh Sivarajan; Juliana Laze; Danil V. Makarov; Herbert Lepor

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.


European Urology | 2014

Robot-assisted Partial Nephrectomy in Patients with Baseline Chronic Kidney Disease: A Multi-institutional Propensity Score-Matched Analysis

Ramesh Kumar; Jesse D. Sammon; Bartosz F. Kaczmarek; Ali Khalifeh; Michael A. Gorin; Ganesh Sivarajan; Youssef S. Tanagho; Sam B. Bhayani; Michael D. Stifelman; Mohamad E. Allaf; Jihad H. Kaouk; Craig G. Rogers

BACKGROUND Robot-assisted partial nephrectomy (RPN) in the setting of chronic kidney disease (CKD) presents additional challenges for the preservation of renal function. OBJECTIVE To evaluate functional outcomes of RPN in patients with CKD relative to patients undergoing RPN without baseline CKD. DESIGN, SETTING, AND PARTICIPANTS A total of 1197 consecutive patients who underwent RPN at five academic institutions between 2007 and 2012 were identified for this descriptive study. A total of 172 patients who underwent RPN with preexisting CKD (estimated glomerular filtration rate [eGFR] of 15-60 ml/min per 1.73 m(2)) were identified. Perioperative results of 121 patients were compared against propensity score-matched controls without CKD (eGFR ≥60 ml/min per 1.73 m(2)). INTERVENTION RPN in patients with or without baseline CKD. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Descriptive statistics and propensity score-matched operative and functional outcomes. RESULTS AND LIMITATIONS After propensity score matching, patients with baseline CKD had a lower percentage eGFR decrease at first follow-up (-5.1 vs -10.9), which remained significant at a mean follow-up of 12.6 mo (-2.8 vs -9.1, p<0.05), and they had less CKD upstaging (11.8% vs 33.1%). CKD patients were less likely to be discharged in the first two postoperative days (39.7% vs 56.2%, p=0.006) and had a higher rate of surgical complications (21.5% vs 10.7%, p=0.007). The retrospective analysis was the main limitation of this study. CONCLUSIONS RPN in patients with baseline CKD is associated with a smaller decrease in renal function compared with patients without baseline CKD, but a higher risk of surgical complications and a longer hospital stay.


Medical Care | 2015

The Effect of the Diffusion of the Surgical Robot on the Hospital-level Utilization of Partial Nephrectomy.

Ganesh Sivarajan; Glen B. Taksler; Dawn Walter; Cary P. Gross; Raul E. Sosa; Danil V. Makarov

IntroductionThe rapid diffusion of the surgical robot has been controversial because of the technology’s high costs and its disputed marginal benefit. Some, however, have suggested that adoption of the robot may have improved care for patients with renal malignancy by facilitating partial nephrectomy, an underutilized, technically challenging procedure believed to be less morbid than radical nephrectomy. We sought to determine whether institutional acquisition of the robot was associated with increased utilization of partial nephrectomy. Methods:We used all payer data from 7 states to identify 21,569 nephrectomies. These patient-level records were aggregated to the hospital-level then merged with the American Hospital Association Annual Survey and publicly available data on timing of robot acquisition. We used a multivariable difference-in-difference model to assess at the hospital-level whether robot acquisition was associated with an increase in the proportion of partial nephrectomy, adjusting for hospital nephrectomy volume, year of surgery, and several additional hospital-level factors. Results:In the multivariable-adjusted differences-in-differences model, hospitals acquiring a robot between 2001 and 2004 performed a greater proportion of partial nephrectomy in both 2005 (29.9% increase) and 2008 (34.9% increase). Hospitals acquiring a robot between 2005 and 2008 also demonstrated a greater proportion of partial nephrectomy in 2008 (15.5% increase). In addition, hospital nephrectomy volume and urban location were also significantly associated with increased proportion of partial nephrectomy. Conclusions:Hospital acquisition of the surgical robot is associated with greater proportion of partial nephrectomy, an underutilized, guideline-encouraged procedure. This is one of the few studies to suggest robot acquisition is associated with improvement in quality of patient care.


Urologic Clinics of North America | 2012

Current Practice Patterns in the Surgical Management of Renal Cancer in the United States

Ganesh Sivarajan; William C. Huang

Over the last two decades, there has been a rising incidence of renal tumors, particularly, small renal masses (<4 cm) resulting in a downward size and stage migration. This has brought about a paradigm shift in the management of newly diagnosed renal masses, such that nephron-sparing surgery, minimally invasive techniques, and active surveillance are frequently considered preferable to the historical gold standard of open radical nephrectomy. Population-based cohort studies indicate, however, that the widespread adoption of these techniques has been relatively slow and incomplete leading to significant disparities in the delivery of care throughout the country. Further investigation is required to determine the barriers to diffusion of new techniques and technology as well as to ensure equal access to quality care in the United States.


Reviews in urology | 2015

Juxta-adrenal Ancient Schwannoma: A Rare Retroperitoneal Tumor.

Daniel Wollin; Ganesh Sivarajan; Pratibha Shukla; Jonathan Melamed; William C. Huang; Herbert Lepor

Retroperitoneal schwannoma is a rare tumor that is often misdiagnosed as malignancy due to a concerning appearance on cross-sectional imaging. Pathology and immunohistochemistry form the gold standard for diagnosis; as such, local excision is the treatment of choice for this disease. We present two cases of juxta-adrenal ancient schwannoma that were treated with adrenalectomy and discuss the current literature regarding this entity.

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Michael A. Gorin

Johns Hopkins University School of Medicine

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