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Dive into the research topics where Vinayak Muralidhar is active.

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Featured researches published by Vinayak Muralidhar.


The Journal of Urology | 2015

Incidence and Predictors of Upgrading and Up Staging among 10,000 Contemporary Patients with Low Risk Prostate Cancer

Kathryn T. Dinh; Brandon A. Mahal; David R. Ziehr; Vinayak Muralidhar; Yu-Wei Chen; Vidya B. Viswanathan; Michelle D. Nezolosky; Clair J. Beard; Toni K. Choueiri; Neil E. Martin; Peter F. Orio; Christopher Sweeney; Quoc-Dien Trinh; Paul L. Nguyen

PURPOSE We determined the incidence of pathological upgrading and up staging for contemporary, clinically low risk patients, and identified predictors of having occult, advanced disease to inform the selection of patients for active surveillance. MATERIALS AND METHODS We studied 10,273 patients in the SEER database diagnosed with clinically low risk disease (cT1c/T2a, prostate specific antigen less than 10 ng/ml, Gleason 3 + 3 = 6) in 2010 to 2011 and treated with prostatectomy. The primary outcome was the incidence of upgrading to pathological Gleason score 7-10 or up staging to pathological T3-T4/N1 disease. Multivariable logistic regression of cases with complete biopsy data (5,581) identified significant predictors of upgrading or up staging, which were then used to create a risk stratification table. RESULTS At prostatectomy 44% of cases were upgraded and 9.7% were up staged. Multivariable analysis of 5,581 patients showed age, prostate specific antigen and percent positive cores (all p < 0.001) but not race were associated with occult, advanced disease. With these variables dichotomized at the median, age older than 60 years (AOR 1.39), prostate specific antigen greater than 5.0 ng/ml (AOR 1.28) and more than 25% positive cores (AOR 1.76) were significantly associated with upgrading (all p < 0.001). Similarly, age older than 60 years (AOR 1.42), prostate specific antigen greater than 5.0 ng/ml (AOR 1.44) and more than 25% positive cores (AOR 2.26) were associated with up staging (all p < 0.001). Overall 60% of 5,581 low risk cases with prostate specific antigen 7.5 to 9.9 ng/ml and more than 25% positive cores were upgraded. This study is limited by possible bias introduced by only using patients selected for prostatectomy. CONCLUSIONS Nearly half of clinically low risk patients harbor Gleason 7 or greater, or pT3 or greater disease, and should be risk stratified by prostate specific antigen and percent positive cores for consideration of further testing before deciding on active surveillance.


Journal of Clinical Oncology | 2016

Association of Androgen Deprivation Therapy With Depression in Localized Prostate Cancer

Kathryn T. Dinh; Gally Reznor; Vinayak Muralidhar; Brandon A. Mahal; Michelle D. Nezolosky; Toni K. Choueiri; Karen E. Hoffman; Jim C. Hu; Christopher Sweeney; Quoc-Dien Trinh; Paul L. Nguyen

PURPOSE Androgen deprivation therapy (ADT) may contribute to depression, yet several studies have not demonstrated a link. We aimed to determine whether receipt of any ADT or longer duration of ADT for prostate cancer (PCa) is associated with an increased risk of depression. METHODS We identified 78,552 men older than age 65 years with stage I to III PCa using the SEER-Medicare-linked database from 1992 to 2006, excluding patients with psychiatric diagnoses within the prior year. Our primary analysis was the association between pharmacologic ADT and the diagnosis of depression or receipt of inpatient or outpatient psychiatric treatment using Cox proportional hazards regression. Drug data for treatment of depression were not available. Our secondary analysis investigated the association between duration of ADT and each end point. RESULTS Overall, 43% of patients (n = 33,882) who received ADT, compared with patients who did not receive ADT, had higher 3-year cumulative incidences of depression (7.1% v 5.2%, respectively), inpatient psychiatric treatment (2.8% v 1.9%, respectively), and outpatient psychiatric treatment (3.4% v 2.5%, respectively; all P < .001). Adjusted Cox analyses demonstrated that patients with ADT had a 23% increased risk of depression (adjusted hazard ratio [AHR], 1.23; 95% CI, 1.15 to 1.31), 29% increased risk of inpatient psychiatric treatment (AHR, 1.29; 95% CI, 1.17 to 1.41), and a nonsignificant 7% increased risk of outpatient psychiatric treatment (AHR, 1.07; 95% CI, 0.97 to 1.17) compared with patients without ADT. The risk of depression increased with duration of ADT, from 12% with ≤ 6 months of treatment, 26% with 7 to 11 months of treatment, to 37% with ≥ 12 months of treatment (P trend < .001). A similar duration effect was seen for inpatient (P trend < .001) and outpatient psychiatric treatment (P trend < .001). CONCLUSION Pharmacologic ADT increased the risk of depression and inpatient psychiatric treatment in this large study of elderly men with localized PCa. This risk increased with longer duration of ADT. The possible psychiatric effects of ADT should be recognized by physicians and discussed with patients before initiating treatment.


International Journal of Radiation Oncology Biology Physics | 2015

Definition and Validation of “Favorable High-Risk Prostate Cancer”: Implications for Personalizing Treatment of Radiation-Managed Patients

Vinayak Muralidhar; Ming-Hui Chen; Gally Reznor; Brian J. Moran; Michelle H. Braccioforte; Clair J. Beard; Felix Y. Feng; Karen E. Hoffman; Toni K. Choueiri; Neil E. Martin; Christopher Sweeney; Quoc-Dien Trinh; Paul L. Nguyen

PURPOSE To define and validate a classification of favorable high-risk prostate cancer that could be used to personalize therapy, given that consensus guidelines recommend similar treatments for all radiation-managed patients with high-risk disease. METHODS AND MATERIALS We studied 3618 patients with cT1-T3aN0M0 high-risk or unfavorable intermediate-risk prostate adenocarcinoma treated with radiation at a single institution between 1997 and 2013. Favorable high-risk was defined as T1c disease with either Gleason 4 + 4 = 8 and prostate-specific antigen <10 ng/mL or Gleason 6 and prostate-specific antigen >20 ng/mL. Competing risks regression was used to determine differences in the risk of prostate cancer-specific mortality (PCSM) after controlling for baseline factors and treatment. Our results were validated in a cohort of 13,275 patients using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. RESULTS Patients with favorable high-risk disease had significantly better PCSM than other men with high-risk disease (adjusted hazard ratio [AHR] 0.42, 95% confidence interval [CI] 0.18-0.996, P=.049) and similar PCSM as men with unfavorable intermediate-risk disease (AHR 1.17, 95% CI 0.50-2.75, P=.710). We observed very similar results within the SEER-Medicare cohort (favorable high-risk vs other high-risk: AHR 0.21, 95% CI 0.11-0.41, P<.001; favorable high-risk vs unfavorable intermediate-risk: AHR 0.67, 95% CI 0.33-1.36, P=.268). CONCLUSIONS Patients with favorable high-risk prostate cancer have significantly better PCSM than other patients with high-risk disease and similar PCSM as those with unfavorable intermediate-risk disease, who are typically treated with shorter-course androgen deprivation therapy. This new classification system may allow for personalization of treatment within high-risk disease, such as consideration of shorter-course androgen deprivation therapy for favorable high-risk disease.


BJUI | 2016

Gleason score 5 + 3 = 8 prostate cancer: much more like Gleason score 9?

Brandon A. Mahal; Vinayak Muralidhar; Y. Chen; Toni K. Choueiri; Karen E. Hoffman; Jim C. Hu; Christopher Sweeney; James B. Yu; Felix Y. Feng; Quoc-Dien Trinh; Paul L. Nguyen

To determine whether patients with Gleason score 5 + 3 = 8 prostate cancer have outcomes more similar to other patients with Gleason score 8 disease or to patients with Gleason score 9 disease.


Otolaryngology-Head and Neck Surgery | 2015

Transfusion in head and neck free flap patients: practice patterns and a comparative analysis by flap type.

Sidharth V. Puram; Bharat B. Yarlagadda; Rosh K. V. Sethi; Vinayak Muralidhar; Kyle J. Chambers; Kevin S. Emerick; James W. Rocco; Derrick T. Lin; Daniel G. Deschler

Objective To characterize patterns of utilization and outcomes following transfusion in head and neck patients undergoing free flap reconstruction. Study Design Case series with chart review. Setting Tertiary academic medical center. Subjects and Methods Two hundred eighty-two head and neck patients undergoing free flap reconstruction from 2011 to 2013. Outcome parameters included post-transfusion hematocrit increase, length of stay (LOS), flap survival, and perioperative complications. Results Of all head and neck free flap patients, 48.9% received blood transfusions. Average pretransfusion hametocrit (Hct) was 24.7% ± 0.2% with 2.5 ± 0.1 units of blood transfused. Transfused patients were more likely to have been taken back to the operating room. Rates of transfusion were similar between flap types, although anterolateral thigh (ALT) and fibular free flap (FFF) patients had higher transfusion requirements compared to radial forearm free flap (RFFF) patients. Further, FFF patients trended toward receiving transfusions earlier. Transfusion did not influence flap survival but was associated with wound dehiscence, myocardial infarction, congestive heart failure, respiratory distress, and pneumonia. Subset analyses by flap type revealed that differences were significant among the RFFF and FFF cohorts but not ALT patients. When comparing patients who were transfused for Hct <21 to those transfused for Hct <27, there were no differences in LOS, flap survival, or postsurgical complications. Conclusions Among the different types of flaps, FFF and ALT are associated with higher transfusion requirements. Transfusion in patients undergoing free flap reconstruction does not significantly affect flap survival but was associated with perioperative complications. Our data support consideration of a restrictive transfusion policy in free flap patients.


Urologic Oncology-seminars and Original Investigations | 2016

Significant increase in prostatectomy and decrease in radiation for clinical T3 prostate cancer from 1998 to 2012

Michelle D. Nezolosky; Kathryn T. Dinh; Vinayak Muralidhar; Brandon A. Mahal; Yu-Wei Chen; Clair J. Beard; Toni K. Choueiri; Neil E. Martin; Christopher Sweeney; Quoc-Dien Trinh; Paul L. Nguyen

PURPOSE We aimed to describe changes in treatment patterns for clinical T3 prostate cancer (PCa) from 1998 to 2012, specifically investigating what factors influence receipt of prostatectomy or radiation. MATERIALS AND METHODS Using the Surveillance, Epidemiology, and End Results database, we studied 11,604 men with clinical T3N0M0 PCa from 1998 to 2012, with treatment categorized as radiation, radical prostatectomy (RP), or no curative therapy. We calculated rate of treatment type by year of diagnosis to investigate trends in treatment patterns, further stratifying by clinical T3a, defined as unilateral and bilateral extracapsular extension (n = 3,842), vs. T3b (defined as extension to seminal vesicles (n = 3,665). Finally, a multivariable logistic regression analysis measured association of demographic and clinical variables with type of treatment received for years 2010 to 2011. RESULTS Rates of prostatectomy increased significantly from 1998 to 2012 (12.5% vs. 44.4%), radiation decreased significantly (55.8% vs. 38.4%), and receipt of no treatment also decreased (31.7% vs. 17.2%, all P<0.001). These trends were similar for clinical T3a and T3b. Rates of prostatectomy surpassed radiation by 2008 in clinical T3a, reaching 49.8% vs. 37.1%, respectively, in 2012 (P = 0.002), and were statistically similar to radiation in 2012 for clinical T3b, reaching 41.6% vs. 42.1% (P = 0.92). Multivariable logistic regression analysis demonstrated that patients were less likely to receive prostatectomy than radiation if biopsy Gleason scores of 8 to 10 (adjusted odds ratio [AOR] = 0.41, 0.32-0.53), higher initial prostate-specific antigen (AOR = 0.97, 0.97-0.98), and older age (AOR = 0.92, 0.90-0.03, all P<0.01). The likelihood of RP was similar among cT3b vs. cT3a (AOR = 0.95, 0.71-1.26, P = 0.74). CONCLUSIONS Since 1998, there has been a significant increase in the use of RP for clinical T3 PCa and a significant decrease in the use of radiation such that in 2012, the use of prostatectomy exceeded the use of radiation.


Urologic Oncology-seminars and Original Investigations | 2017

Maximizing resources in the local treatment of prostate cancer: A summary of cost-effectiveness studies

Vinayak Muralidhar; Paul L. Nguyen

OBJECTIVES Prostate cancer is a common diagnosis with several treatment options for the newly diagnosed patient, including radiation, surgery, active surveillance, and watchful waiting. Although tailoring of treatment to individual patient needs is an important goal, the recent passage of the Affordable Care Act has placed renewed interest in cost containment and cost-effectiveness. We sought to conduct a literature review of recent US-based studies to analyze the cost-effectiveness of initial local treatments for localized prostate cancer. METHODS We conducted a systematic literature search through PubMed, the Cost-Effectiveness Analysis Registry, and manual cross-referencing of articles. We identified US-based studies with cost analyses starting in 2005 that studied the cost-effectiveness of initial local treatments for localized prostate cancer (surgery, radiation, or observation). RESULTS There were eight studies that met our inclusion and exclusion criteria. Most studies took the cost perspective of Medicare, and two studies also considered the societal cost in terms of lost patient time. Most studies also used a Markov model with inputs based on the available literature for the effectiveness and toxicity of the different treatment options. The radiation-focused studies tended to find brachytherapy (BT) or stereotactic body radiation therapy (SBRT) to be more cost-effective than intensity-modulated radiation therapy or proton beam therapy. These findings were primarily based on the lower cost of SBRT or BT with roughly equal efficacy and toxicity. The two studies focused on surgery found surgery to be more cost effective than intensity-modulated radiation therapy, at least for low-risk disease, and one study found BT to be more cost-effective than surgery, and watchful waiting to be the most cost-effective option overall. CONCLUSION Cost-effectiveness analysis is important because it helps patients, physicians, and policymakers make quantitatively-based decisions, which balance treatment efficacy, toxicity, and costs. Significant methodological heterogeneity in the studies we found limit the ability to compare their results directly, but most found that for favorable-risk prostate cancer, shorter or simpler treatments tended to be more cost-effective, including no treatment (watchful waiting) in one study.


Cancer | 2016

National trends and determinants of proton therapy use for prostate cancer: A National Cancer Data Base study.

Brandon A. Mahal; Y. Chen; Jason A. Efstathiou; Vinayak Muralidhar; Karen E. Hoffman; James B. Yu; Felix Y. Feng; Clair J. Beard; Neil E. Martin; Peter F. Orio; Paul L. Nguyen

In the current study, the authors sought to both characterize the national trends in proton therapy use for prostate cancer and determine the factors associated with receipt of this limited resource, using what to the best of their knowledge is the largest nationwide cancer registry.


Cancer | 2017

Impact of ethnicity on the outcome of men with metastatic, hormone-sensitive prostate cancer

Brandon David Bernard; Vinayak Muralidhar; Yu-Hui Chen; Srikala S. Sridhar; Edith P. Mitchell; Curtis A. Pettaway; Michael A. Carducci; Paul L. Nguyen; Christopher Sweeney

Prostate cancer (PCa) outcomes are impacted by socioeconomic and biologic factors. Ethnicity plays a role in the former, but little is known about the responsiveness of metastatic PCa to androgen‐deprivation therapy (ADT) among races.


Journal of Contemporary Brachytherapy | 2016

Brachytherapy boost and cancer-specific mortality in favorable high-risk versus other high-risk prostate cancer

Vinayak Muralidhar; Michael Xiang; Peter F. Orio; Neil E. Martin; Clair J. Beard; Felix Y. Feng; Karen E. Hoffman; Paul L. Nguyen

Purpose Recent retrospective data suggest that brachytherapy (BT) boost may confer a cancer-specific survival benefit in radiation-managed high-risk prostate cancer. We sought to determine whether this survival benefit would extend to the recently defined favorable high-risk subgroup of prostate cancer patients (T1c, Gleason 4 + 4 = 8, PSA < 10 ng/ml or T1c, Gleason 6, PSA > 20 ng/ml). Material and methods We identified 45,078 patients in the Surveillance, Epidemiology, and End Results database with cT1c-T3aN0M0 intermediate- to high-risk prostate cancer diagnosed 2004-2011 treated with external beam radiation therapy (EBRT) only or EBRT plus BT. We used multivariable competing risks regression to determine differences in the rate of prostate cancer-specific mortality (PCSM) after EBRT + BT or EBRT alone in patients with intermediate-risk, favorable high-risk, or other high-risk disease after adjusting for demographic and clinical factors. Results EBRT + BT was not associated with an improvement in 5-year PCSM compared to EBRT alone among patients with favorable high-risk disease (1.6% vs. 1.8%; adjusted hazard ratio [AHR]: 0.56; 95% confidence interval [CI]: 0.21-1.52, p = 0.258), and intermediate-risk disease (0.8% vs. 1.0%, AHR: 0.83, 95% CI: 0.59-1.16, p = 0.270). Others with high-risk disease had significantly lower 5-year PCSM when treated with EBRT + BT compared with EBRT alone (3.9% vs. 5.3%; AHR: 0.73; 95% CI: 0.55-0.95; p = 0.022). Conclusions Brachytherapy boost is associated with a decreased rate of PCSM in some men with high-risk prostate cancer but not among patients with favorable high-risk disease. Our results suggest that the recently-defined “favorable high-risk” category may be used to personalize therapy for men with high-risk disease.

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Paul L. Nguyen

Brigham and Women's Hospital

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Neil E. Martin

Brigham and Women's Hospital

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Quoc-Dien Trinh

Brigham and Women's Hospital

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Clair J. Beard

Brigham and Women's Hospital

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