Publications by authors named "William Tabayoyong"

Objective: To evaluate the predictive validity of IRIS™ (Intuitive Surgical®, Sunnyvale, CA, USA) as a planning tool for robot-assisted partial nephrectomy (RAPN) by assessing the degree of overlap with intraoperative execution.

Methods: Thirty-one patients scheduled for RAPN by four experienced urologists were enrolled in a prospective study. Prior to surgery, urologists reviewed the IRIS™ three-dimensional model on an iphone Operating System (iOS) app and completed a questionnaire outlining their surgical plan including surgical approach, and ischemia technique as well as confidence in executing this plan.

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Background: Improving clinical trial design is important for optimizing approval of safe and effective drugs. Phase 1 clinical trials seek to determine phase 2 doses by investigating predefined dose-limiting toxicities. Traditional definitions of dose-limiting toxicity may not be applicable to intravesical therapies for bladder cancer.

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With introduction of the da Vinci single-port (SP) system, we evaluated which multiport (MP) robotic skills are naturally transferable to the SP platform. Three groups of urologists: Group 1 (5 inexperienced in MP and SP), Group 2 (5 experienced in MP without SP experience), and Group 3 (2 experienced in both MP and SP) were recruited to complete a validated urethrovesical anastomosis simulation using MP followed by SP robots. Performance was graded using both GEARS and RACE scales.

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Purpose: IRIS provides interactive, 3D anatomical visualizations of renal anatomy for pre-operative planning that can be manipulated by altering transparency, rotating, zooming, panning, and overlaying the CT scan. Our objective was to analyze how eye tracking metrics and utilization patterns differ between preoperative surgical planning of renal masses using IRIS and CT scans.

Methods: Seven surgeons randomly reviewed IRIS and CT images of 9 patients with renal masses [5 high complexity (RENAL score ≥ 8), 4 low complexity (≤ 7)].

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Objective: To evaluate the use of 3D computed aided designs and 3D-printed models as pre-operative planning tools for urologists, in addition to radiologist interpreted mp-MRIS, prior to radical prostatectomy procedures.

Methods: Ten patients with biopsy-positive lesions detected on mp-MRI were retrospectively selected. Radiologists identified lesion locations using a Prostate Imaging-Reporting and Data System (PI-RADS) map and segmented the prostate, lesion(s), and surrounding anatomy to create 3D-CADs and 3D-printed models for each patient.

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Purpose: The American Urological Association (AUA) introduced evidence-based guidelines for the management of nonmuscle invasive bladder cancer (NMIBC) in 2016. We sought to assess the implementation of these guidelines among members of the Society of Urologic Oncology (SUO) with an aim to identifying addressable gaps.

Methods And Materials: An SUO approved survey was distributed to 747 members from December 28, 2018 to February 2, 2019.

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Background: Tumors that recur after bacillus Calmette-Guerin (BCG) therapy are considered to be of very high risk, and patients are often recommended to undergo radical cystectomy (RC). However, the nuances associated with the grade of tumor recurrence after BCG treatment are not well understood.

Objective: To characterize the pattern of bladder cancer progression and cancer-specific survival (CSS) in patients with recurrences dichotomized by low grade (LG) versus high grade (HG) after intravesical BCG treatment, and to assess the safety of continued bladder-sparing therapy in these patients.

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Purpose Of Review: We summarize the current literature regarding the available urinary biomarkers for the detection and surveillance of bladder cancer.

Recent Findings: Four urinary biomarkers have FDA approval for the detection of bladder cancer; however, they have not supplanted cystoscopy and urine cytology as the gold standard. Recent technological advances in next-generation sequencing have allowed the field of urinary biomarker research to move beyond protein biomarkers and now include genomic, transcriptomic, and epigenetic panels.

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The category "BCG-unresponsive disease", formulated by experts at the request of the United States Food and Drug Administration, denotes a group of patients with recurrent non-muscle-invasive bladder cancer for whom continued BCG treatment is unlikely to provide benefit. Although quickly adopted for trial design, many of the nuances within the definition lack validation. In this study, we evaluated the prognostic value of BCG unresponsive designation (i.

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Context: Current guidelines remain ill-defined regarding the optimal intravesical chemotherapy type and regimen for the treatment of non-muscle-invasive bladder cancer (NMIBC). Although maintenance therapy is a standard part of bacillus Calmette-Guerin (BCG) therapy, its role in the context of chemotherapy remains debatable.

Objective: We reviewed the literature regarding the utilization of intravesical maintenance chemotherapy in the treatment of NMIBC to determine its impact on recurrence, progression, and survival.

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Introduction: We sought to prospectively evaluate the effectiveness of the multidisciplinary tumour board (MTB) on altering treatment plans for genitourinary (GU) cancer patients.

Methods: All GU cancer patients seen at our tertiary care hospital are discussed at MTB. We prospectively collected data on adult patients discussed over a continuous, 20-month period.

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Radical cystectomy with bilateral pelvic lymph node dissection is the standard of care for patients with clinically localized muscle-invasive bladder cancer. Survival after radical cystectomy is associated with final pathologic staging. Survival decreases with increasing pT stage because of the presence of occult micrometastases, indicating the need for systemic chemotherapy.

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Purpose Of Review: Recent Food and Drug Administration (FDA) approval of five new immune checkpoint inhibitors for the treatment of metastatic urothelial cancer represents the first major treatment breakthrough for this disease since the introduction of combination chemotherapy over 30 years ago. This review examines the recent clinical trials leading to FDA approval of these agents, the current challenges facing immunotherapy and areas that require further research.

Recent Findings: The programmed death 1 receptor (PD-1) and its ligand programmed death ligand-1 (PD-L1) are important negative regulators of immune activity, preventing destruction of normal tissues and autoimmunity.

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Introduction: To determine tumour, patient, and provider factors associated with cytoreductive nephrectomy (CN) use and to identify those factors that predicted short-term and long-term surgical outcomes.

Methods: We performed a retrospective review (1998-2011) of the National Cancer Database, a U.S.

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Purpose To develop and evaluate an examination consisting of magnetic resonance (MR) fingerprinting-based T1, T2, and standard apparent diffusion coefficient (ADC) mapping for multiparametric characterization of prostate disease. Materials and Methods This institutional review board-approved, HIPAA-compliant retrospective study of prospectively collected data included 140 patients suspected of having prostate cancer. T1 and T2 mapping was performed with fast imaging with steady-state precession-based MR fingerprinting with ADC mapping.

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Prostate cancer is the most common malignancy diagnosed in men and the second leading cause of cancer death for men in the United States. Widespread use of prostate-specific antigen (PSA) screening led to a decrease in mortality; however, PSA screening may have led to overdiagnosis and overtreatment of clinically insignificant cancers. The US Preventive Services Task Force (USPSTF) released a statement recommending against the use of PSA, which was met with concern from professional organizations.

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Article Synopsis
  • This study evaluated the surgical margin status in patients with clinical T1a renal cell carcinoma who underwent different types of partial nephrectomy (open, laparoscopic, robotic) using data from the National Cancer Database between 2010 and 2011.
  • A total of 11,587 patients were analyzed, revealing that laparoscopic and robotic approaches had significantly higher rates of positive surgical margins (8.1% and 8.7% respectively) compared to open surgery (4.9%).
  • The findings suggest that laparoscopic and robotic surgeries may pose a greater risk for positive surgical margins, prompting further research on how these margins impact long-term cancer outcomes.
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Embryonic stem (ES) cells are a novel source of cells, especially hematopoietic progenitor cells that can be used to treat degenerative diseases in humans. However, there is a need to determine how ES cell-derived progenitors are regulated by both the adaptive and innate immune systems post transplantation. In this study, we demonstrate that hematopoietic progenitor cells (HPCs) derived from mouse ES cells ectopically expressing HOXB4 fail to engraft long-term in the presence of NK cells.

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Background: Achieving transplantation tolerance remains an unresolved clinical challenge. Although bone marrow transplantation (BMT) induces mixed chimerism that establishes transplantation tolerance, the preconditioning regimens required for BMT to succeed are too prohibitive for routine use. Recently, embryonic stem (ES) cells have emerged as a potential alternative cell source to bone marrow cells.

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The goal of this editorial is to revisit soluble human leukocyte antigens (sHLA) and to highlight the findings reported by Albitar et al. in this issue on the relation between sHLA levels in Non-Hodgkin's Lymphoma (NHL) and Hodgkin's Disease (HD). We will review key aspects of sHLA including soluble HLA-G, which has received a lot of attention in recent publications.

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Transforming growth factor B (TGF-beta) is a potent immunosuppressive cytokine that is frequently associated with mechanisms of tumor escape from immunosurveillance. We report that transplantation of murine bone marrow (BM) expressing a dominant-negative TGF-beta type II receptor (TbetaRIIDN) leads to the generation of mature leukocytes capable of a potent antitumor response in vivo. Hematopoietic precursors in murine BM from donor mice were rendered insensitive to TGF-beta via retroviral expression of the TbetaRIIDN construct and were transplanted in C57BL/6 mice before tumor challenge.

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TGF-beta regulation of immune homeostasis has been investigated in the context of cytokine knockout (TGF-beta null) mice, in which particular TGF-beta isoforms are disrupted throughout the entire organism, as well as in B and T cell-specific transgenic models, but to date the immunoregulatory effects of TGF-beta have not been addressed in the context of an in vivo mouse model in which multi-isoform TGF-beta signaling is abrogated in multiple leukocyte lineages while leaving nonhemopoietic tissue unaffected. Here we report the development of a murine model of TGF-beta insensitivity limited to the hemopoietic tissue of adult wild-type C57BL/6 mice based on retroviral-mediated gene transfer of a dominant negative TGF-beta type II receptor targeting murine bone marrow. Unlike the lymphoproliferative syndrome observed in TGF-beta1-deficient mice, the disruption of TGF-beta signaling in bone marrow-derived cells leads to dramatic expansion of myeloid cells, primarily monocytes/macrophages, and is associated with cachexia and mortality in lethally irradiated mice reconstituted with dominant negative receptor-transduced bone marrow.

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