8 results on '"Leppert, John T."'
Search Results
2. Trends and perioperative outcomes for laparoscopic and robotic nephrectomy using the National Surgical Quality Improvement Program (NSQIP) database 1 [1] Financial Support: JTL is supported by Award no. DK089086 from the National Institutes of Health (NIH), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
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Liu, Jen-Jane, Leppert, John T., Maxwell, Bryan G., Panousis, Periklis, and Chung, Benjamin I.
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LAPAROSCOPIC surgery , *SURGICAL robots , *NEPHRECTOMY , *HEALTH outcome assessment , *RENAL cancer treatment ,ONCOLOGIC surgery complications - Abstract
Abstract: Objectives: We sought to examine the trends in perioperative outcomes of kidney cancer surgery stratified by type (radical nephrectomy [RN] vs. partial nephrectomy [PN]) and approach (open vs. minimally invasive). Methods: We queried the National Surgical Quality Improvement Program database to identify kidney cancer operations performed from 2005 to 2011. We examined 30-day perioperative outcomes including operative time, transfusion rate, length of stay, major morbidity (cardiovascular, pulmonary, renal, and infectious), and mortality. Results: A total of 2,902 PN and 5,459 RN cases were identified. The use of PN increased over time, accounting for 39% of all nephrectomies in 2011. Minimally invasive approaches also increased over time for both RN and PN. Open surgery was associated with increased length of stay, receipt of transfusion, major complications, and perioperative mortality. Resident involvement and open approach were independent predictors of major complications for both PN and RN. Additionally, the presence of a medical comorbidity was also a risk factor for complications after RN. The overall complication rates decreased for all approaches over the study period. Conclusions: Minimally invasive approaches to kidney cancer renal surgery have increased with favorable outcomes. The safety of open and minimally invasive PN improved significantly over the study period. Although pathologic features cannot be determined from this data set, these data show that complications from renal surgical procedures are decreasing in an era of increasing use. [Copyright &y& Elsevier]
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- 2014
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3. The sensitivity of testosterone immunoassays and their role in monitoring antiandrogen therapy
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Leppert, John T., Lam, John S., Butch, Anthony W., and Belldegrun, Arie S.
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- 2006
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4. The impact of life expectancy on cost-effectiveness of treatment options for clinically localized prostate cancer.
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Naser-Tavakolian, Aurash, Venkataramana, Abhishek, Spiegel, Brennan, Almario, Christopher, Kokorowski, Paul, Freedland, Stephen J., Anger, Jennifer T., Leppert, John T., and Daskivich, Timothy J.
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LIFE expectancy , *PROSTATE cancer , *COST effectiveness , *MONTE Carlo method , *WATCHFUL waiting , *DISEASE risk factors - Abstract
• Cost-effectiveness analysis of therapies for low/intermediate-risk prostate cancer across range of life expectancies. • Active surveillance dominates surgery/radiation (more effective and less costly) when life expectancy is <10 years in both low and intermediate-risk prostate cancer. • For longer life expectancy, active surveillance fails to dominate primarily due to its high cost. • Active surveillance costs for men with longer life expectancy must be reduced. Life expectancy (LE) impacts effectiveness and morbidity of prostate cancer (CaP) treatment, but its impact on cost-effectiveness is unknown. We sought to evaluate the impact of LE on the cost-effectiveness of radical prostatectomy (RP), radiation therapy (RT), and active surveillance (AS) for clinically localized disease. We created a Markov model to calculate incremental cost-effectiveness ratios (ICERs) for RP, RT, and AS over a 20-year time horizon from a Medicare payer perspective for low- and intermediate-risk CaP. Mortality outcomes varied by tumor risk and PCCI score, a validated proxy for LE. We performed 1,000 Monte Carlo simulations with 1-way sensitivity analyses of PCCI within each tumor risk subgroup to compare cost/quality-adjusted life years (QALYs) between treatments. AS dominated RP and RT for low- and intermediate-risk disease in men with LE ≤10 years (PCCI ≥7 and ≥9, respectively). However, AS failed to dominate RP and RT for men with longer LE. For men with low-risk cancer and LE>10 years (PCCI 0–6), AS had the greatest effectiveness, but failed to dominate due to higher cost relative to RP. For men with intermediate-risk cancer with LE>10 years, AS failed to dominate due to higher cost relative to RP (PCCI 0–8) and lower effectiveness relative to RT (PCCI 0–3). The range of QALYs between RP, RT, and AS varied <13% (range: 0%–12.9%) while costs varied up to 521% (range 0.5%–521%) across PCCI scores. LE strongly modulates the cost of CaP treatments. This results in AS dominating RP and RT in men with LE ≤10 years. However, in men with longer LE, AS fails to dominate primarily due to its high cumulative costs, underscoring the need for risk-adjusted AS protocols. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Clinical laboratory tests associated with survival in patients with metastatic renal cell carcinoma: A Laboratory Wide Association Study (LWAS).
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Velaer, Kyla, Thomas, I-Chun, Yang, Jaden, Kapphahn, Kristopher, Metzner, Thomas J., Golla, Abhinav, Hoerner, Christian R., Fan, Alice C., Master, Viraj, Chertow, Glenn M., Brooks, James D., Patel, Chirag J., Desai, Manisha, and Leppert, John T.
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RENAL cell carcinoma , *OVERALL survival , *ACUTE phase proteins , *PATHOLOGICAL laboratories , *PROGNOSTIC models , *BIOMARKERS - Abstract
Background: Prognostic models for patients with metastatic renal cell carcinoma (mRCC) include select laboratory values. These models have important limitations, including reliance on a limited array of laboratory tests, and use of dichotomous ("high-low") cutoffs. We applied a Laboratory-Wide Association Study (LWAS) framework to systematically evaluate common clinical laboratory results associated with survival for patients diagnosed with mRCC.Methods: We used laboratory data for 3,385 patients diagnosed with mRCC from 2002 to 2017. We developed a LWAS framework, to examine the association with 53 common clinical laboratory tests results (641,712 measurements) and overall survival. We employed false-discovery rate to test the association of multiple laboratory tests with survival, and validated these results using 3 separate cohorts to generate a standardized hazard ratio (sHR), reported for a 1 standard deviation unit change in each laboratory test.Results: The LWAS approach confirmed the association of laboratory values currently used in prognostic models with survival, including calcium (HR 1.35, 95%CI 1.24-1.48), leukocyte count (HR 1.40, 95%CI 1.30-1.51), platelet count (HR 1.36, 95%CI 1.27-1.51), and hemoglobin (HR 0.79, 95%CI 0.72-0.86). Use of these tests as continuous variables improved model performance. LWAS also identified acute phase reactants associated with survival not typically included in prognostic models, including serum albumin (HR 0.66, 95%CI 0.61-0.72), ferritin (HR 1.25, 95%CI 1.08-1.45), alkaline phosphatase (HR 1.31, 95%CI 1.23-1.40), and C-reactive protein (HR 1.70, 95%CI 1.14-2.53).Conclusions: Routinely measured laboratory tests can refine current prognostic models, facilitate comparisons across clinical trial cohorts, and match patients with specific systemic therapies. [ABSTRACT FROM AUTHOR]- Published
- 2022
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6. Life expectancy estimates for patients diagnosed with prostate cancer in the Veterans Health Administration.
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Sohlberg, Ericka M., Thomas, I-Chun, Yang, Jaden, Kapphahn, Kristopher, Daskivich, Timothy J., Skolarus, Ted A., Shelton, Jeremy B., Makarov, Danil V., Bergman, Jonathan, Bang, Christine Ko, Goldstein, Mary K., Wagner, Todd H., Brooks, James D., Desai, Manisha, and Leppert, John T.
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HEALTH services administration , *LIFE expectancy , *PROSTATE cancer patients , *VETERANS' health , *PROPORTIONAL hazards models , *CASTRATION-resistant prostate cancer - Abstract
Purpose: Accurate life expectancy estimates are required to inform prostate cancer treatment decisions. However, few models are specific to the population served or easily implemented in a clinical setting. We sought to create life expectancy estimates specific to Veterans diagnosed with prostate cancer.Materials and Methods: Using national Veterans Health Administration electronic health records, we identified Veterans diagnosed with prostate cancer between 2000 and 2015. We abstracted demographics, comorbidities, oncologic staging, and treatment information. We fit Cox Proportional Hazards models to determine the impact of age, comorbidity, cancer risk, and race on survival. We stratified life expectancy estimates by age, comorbidity and cancer stage.Results: Our analytic cohort included 145,678 patients. Survival modeling demonstrated the importance of age and comorbidity across all cancer risk categories. Life expectancy estimates generated from age and comorbidity data were predictive of overall survival (C-index 0.676, 95% CI 0.674-0.679) and visualized using Kaplan-Meier plots and heatmaps stratified by age and comorbidity. Separate life expectancy estimates were generated for patients with localized or advanced disease. These life expectancy estimates calibrate well across prostate cancer risk categories.Conclusions: Life expectancy estimates are essential to providing patient-centered prostate cancer care. We developed accessible life expectancy estimation tools for Veterans diagnosed with prostate cancer that can be used in routine clinical practice to inform medical-decision making. [ABSTRACT FROM AUTHOR]- Published
- 2020
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7. Optical biopsy of penile cancer with in vivo confocal laser endomicroscopy.
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Shkolyar, Eugene, Laurie, Mark A., Mach, Kathleen E., Trivedi, Dharati R., Zlatev, Dimitar V., Chang, Timothy C., Metzner, Thomas J., Leppert, John T., Kao, Chia-Sui, and Liao, Joseph C.
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PENILE cancer , *CONFOCAL microscopy , *CELL membranes , *LASERS , *BIOPSY , *SURGICAL site , *CELL size - Abstract
Introduction: Surgical management of penile cancer depends on accurate margin assessment and staging. Advanced optical imaging technologies may improve penile biopsy and organ-sparing treatment. We evaluated the feasibility of confocal laser endomicroscopy for intraoperative assessment of benign and malignant penile tissue.Patients and Methods: With institutional review board approval, 11 patients were recruited, 9 with suspected penile cancer, and 2 healthy controls. Confocal laser endomicroscopy using a 2.6-mm fiber-optic probe was performed at 1 or 2 procedures on all subjects, for 13 imaging procedures. Fluorescein was administered intravenously approximately 3 minutes prior to imaging for contrast. Video sequences from in vivo (n = 12) and ex vivo (n = 6) imaging were obtained of normal glans, suspicious lesions, and surgical margins. Images were processed, annotated, characterized, and correlated with standard hematoxylin and eosin histopathology.Results: No adverse events related to imaging were reported. Distinguishing features of benign and malignant penile tissue could be identified by confocal laser endomicroscopy. Normal skin had cells of uniform size and shape, with distinct cytoplasmic membranes consistent with squamous epithelium. Malignant lesions were characterized by disorganized, crowded cells of various size and shape, lack of distinct cytoplasmic membranes, and hazy, moth-eaten appearance. The transition from normal to abnormal squamous epithelium could be identified.Conclusions: We report the initial feasibility of intraoperative confocal laser endomicroscopy for penile cancer optical biopsy. Pending further evaluation, confocal laser endomicroscopy could serve as an adjunct or replacement to conventional frozen section pathology for management of penile cancer. [ABSTRACT FROM AUTHOR]- Published
- 2019
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8. Applying the PRECISION approach in biopsy naïve and previously negative prostate biopsy patients.
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Wang, Nancy N., Teslovich, Nikola C., Fan, Richard E., Ghanouni, Pejman, Leppert, John T., Brooks, James D., Ahmadi, Sarir, and Sonn, Geoffrey A.
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PROSTATE biopsy , *BIOPSY , *MAGNETIC resonance imaging - Abstract
Objectives: The PRECISION trial provides level 1 evidence supporting prebiopsy multiparametric magnetic resonance imaging (mpMRI) followed by targeted biopsy only when mpMRI is abnormal [1]. This approach reduced over-detection of low-grade cancer while increasing detection of clinically significant cancer (CSC). Still, important questions remain regarding the reproducibility of these findings outside of a clinical trial and quantifying missed CSC diagnoses using this approach. To address these issues, we retrospectively applied the PRECISION strategy in men who each underwent prebiopsy mpMRI followed by systematic and targeted biopsy.Methods and Materials: Clinical, imaging, and pathology data were prospectively collected from 358 biopsy naïve men and 202 men with previous negative biopsies. To apply the PRECISION approach, a retrospective analysis was done comparing the cancer yield from 2 diagnostic strategies: (1) mpMRI followed by targeted biopsy alone for men with Prostate Imaging Reporting and Data System ≥ 3 lesions and (2) systematic biopsy alone for all men. Primary outcomes were biopsies avoided and the proportion of CSC cancer (Grade Group 2-5) and non-CSC (Grade Group 1).Results: In biopsy naïve patients, the mpMRI diagnostic strategy would have avoided 19% of biopsies while detecting 2.5% more CSC (P= 0.480) and 12% less non-CSC (P< 0.001). Thirteen percent (n= 9) of men with normal mpMRI had CSC on systematic biopsy. For previous negative biopsy patients, the mpMRI diagnostic strategy avoided 21% of biopsies, while detecting 1.5% more CSC (P= 0.737) and 13% less non-CSC (P< 0.001). Seven percent (n= 3) of men with normal mpMRI had CSC on systematic biopsy.Conclusions: Our results provide external validation of the PRECISION finding that mpMRI followed by targeted biopsy of suspicious lesions reduces biopsies and over-diagnosis of low-grade cancer. Unlike PRECISION, we did not find increased diagnosis of CSC. This was true in both biopsy naïve and previously negative biopsy cohorts. We have incorporated this information into shared decision making, which has led some men to choose to avoid biopsy. However, we continue to recommend targeted and systematic biopsy in men with abnormal MRI. [ABSTRACT FROM AUTHOR]- Published
- 2019
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