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Featured researches published by Anthony L. Asher.


JAMA | 2016

Effect of Radiosurgery Alone vs Radiosurgery With Whole Brain Radiation Therapy on Cognitive Function in Patients With 1 to 3 Brain Metastases: A Randomized Clinical Trial

Paul D. Brown; Kurt A. Jaeckle; Karla V. Ballman; Elana Farace; Jane H. Cerhan; S. Keith Anderson; Xiomara W. Carrero; Fred G. Barker; Richard L. Deming; Stuart H. Burri; Cynthia Ménard; Caroline Chung; Volker W. Stieber; Bruce E. Pollock; Evanthia Galanis; Jan C. Buckner; Anthony L. Asher

IMPORTANCE Whole brain radiotherapy (WBRT) significantly improves tumor control in the brain after stereotactic radiosurgery (SRS), yet because of its association with cognitive decline, its role in the treatment of patients with brain metastases remains controversial. OBJECTIVE To determine whether there is less cognitive deterioration at 3 months after SRS alone vs SRS plus WBRT. DESIGN, SETTING, AND PARTICIPANTS At 34 institutions in North America, patients with 1 to 3 brain metastases were randomized to receive SRS or SRS plus WBRT between February 2002 and December 2013. INTERVENTIONS The WBRT dose schedule was 30 Gy in 12 fractions; the SRS dose was 18 to 22 Gy in the SRS plus WBRT group and 20 to 24 Gy for SRS alone. MAIN OUTCOMES AND MEASURES The primary end point was cognitive deterioration (decline >1 SD from baseline on at least 1 cognitive test at 3 months) in participants who completed the baseline and 3-month assessments. Secondary end points included time to intracranial failure, quality of life, functional independence, long-term cognitive status, and overall survival. RESULTS There were 213 randomized participants (SRS alone, n = 111; SRS plus WBRT, n = 102) with a mean age of 60.6 years (SD, 10.5 years); 103 (48%) were women. There was less cognitive deterioration at 3 months after SRS alone (40/63 patients [63.5%]) than when combined with WBRT (44/48 patients [91.7%]; difference, -28.2%; 90% CI, -41.9% to -14.4%; P < .001). Quality of life was higher at 3 months with SRS alone, including overall quality of life (mean change from baseline, -0.1 vs -12.0 points; mean difference, 11.9; 95% CI, 4.8-19.0 points; P = .001). Time to intracranial failure was significantly shorter for SRS alone compared with SRS plus WBRT (hazard ratio, 3.6; 95% CI, 2.2-5.9; P < .001). There was no significant difference in functional independence at 3 months between the treatment groups (mean change from baseline, -1.5 points for SRS alone vs -4.2 points for SRS plus WBRT; mean difference, 2.7 points; 95% CI, -2.0 to 7.4 points; P = .26). Median overall survival was 10.4 months for SRS alone and 7.4 months for SRS plus WBRT (hazard ratio, 1.02; 95% CI, 0.75-1.38; P = .92). For long-term survivors, the incidence of cognitive deterioration was less after SRS alone at 3 months (5/11 [45.5%] vs 16/17 [94.1%]; difference, -48.7%; 95% CI, -87.6% to -9.7%; P = .007) and at 12 months (6/10 [60%] vs 17/18 [94.4%]; difference, -34.4%; 95% CI, -74.4% to 5.5%; P = .04). CONCLUSIONS AND RELEVANCE Among patients with 1 to 3 brain metastases, the use of SRS alone, compared with SRS combined with WBRT, resulted in less cognitive deterioration at 3 months. In the absence of a difference in overall survival, these findings suggest that for patients with 1 to 3 brain metastases amenable to radiosurgery, SRS alone may be a preferred strategy. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00377156.


Journal of Neurosurgery | 2010

Poor drug distribution as a possible explanation for the results of the PRECISE trial

John H. Sampson; Gary E. Archer; Christoph Pedain; Eva Wembacher-Schröder; Manfred Westphal; Sandeep Kunwar; Michael A. Vogelbaum; April Coan; James E. Herndon; Raghu Raghavan; Martin L. Brady; David A. Reardon; Allan H. Friedman; Henry S. Friedman; M. Inmaculada Rodríguez-Ponce; Susan M. Chang; Stephan Mittermeyer; Davi Croteau; Raj K. Puri; James M. Markert; Michael D. Prados; Thomas C. Chen; Adam N. Mamelak; Timothy F. Cloughesy; John S. Yu; Kevin O. Lillehei; Joseph M. Piepmeier; Edward Pan; Frank D. Vrionis; H. Lee Moffitt

OBJECT Convection-enhanced delivery (CED) is a novel intracerebral drug delivery technique with considerable promise for delivering therapeutic agents throughout the CNS. Despite this promise, Phase III clinical trials employing CED have failed to meet clinical end points. Although this may be due to inactive agents or a failure to rigorously validate drug targets, the authors have previously demonstrated that catheter positioning plays a major role in drug distribution using this technique. The purpose of the present work was to retrospectively analyze the expected drug distribution based on catheter positioning data available from the CED arm of the PRECISE trial. METHODS Data on catheter positioning from all patients randomized to the CED arm of the PRECISE trial were available for analyses. BrainLAB iPlan Flow software was used to estimate the expected drug distribution. RESULTS Only 49.8% of catheters met all positioning criteria. Still, catheter positioning score (hazard ratio 0.93, p = 0.043) and the number of optimally positioned catheters (hazard ratio 0.72, p = 0.038) had a significant effect on progression-free survival. Estimated coverage of relevant target volumes was low, however, with only 20.1% of the 2-cm penumbra surrounding the resection cavity covered on average. Although tumor location and resection cavity volume had no effect on coverage volume, estimations of drug delivery to relevant target volumes did correlate well with catheter score (p < 0.003), and optimally positioned catheters had larger coverage volumes (p < 0.002). Only overall survival (p = 0.006) was higher for investigators considered experienced after adjusting for patient age and Karnofsky Performance Scale score. CONCLUSIONS The potential efficacy of drugs delivered by CED may be severely constrained by ineffective delivery in many patients. Routine use of software algorithms and alternative catheter designs and infusion parameters may improve the efficacy of drugs delivered by CED.


Journal of Neuro-oncology | 2003

Safety, Tolerability, and Tumor Response of IL4-Pseudomonas Exotoxin (NBI-3001) in Patients with Recurrent Malignant Glioma

Friedrich Weber; Anthony L. Asher; Richard D. Bucholz; Mitchel S. Berger; Michael D. Prados; Susan M. Chang; Jeffrey N. Bruce; Walter A. Hall; Nikolai G. Rainov; Manfred Westphal; Ronald E. Warnick; Robert W. Rand; Frank Floeth; Frank Rommel; Henry Pan; Vijay N. Hingorani; Raj K. Puri

SummaryPurpose: This was an open-label, dose-escalation trial of intratumoral administration of IL-4Pseudomonas exotoxin (NBI-3001) in patients with recurrent malignant glioma. Patients and methods: A total of 31 patients with histologically verified supratentorial grades 3 and 4 astrocytoma were studied. Of these, 25 patients were diagnosed with glioblastoma multiforme (GBM) while six were diagnosed with anaplastic astrocytoma. Patients were over 18 years of age and had Karnofsky performance scores ≥60. Patients were assigned to one of four dose groups in a dose-escalation fashion: 6 µg/ml × 40 ml, 9 µg/ml × 40 ml, 15 µg/ml × 40 ml, or 9 µg/ml × 100 ml of NBI-3001 administered via convection-enhanced delivery intratumorally using stereotactically placed catheters. Patients were followed with serial MRI scans and clinical assessments every four weeks for the first 16 weeks and then every eight weeks until week 26. Results: No drug-related systemic toxicity, as evident by lack of hematological or serum chemical changes, was apparent in any patients; treatment-related adverse effects were limited to the central nervous system. No deaths were attributable to treatment. Drug-related grade 3 or 4 toxicity was seen in 39% of patients in all dose groups and 22% of patients at the maximum tolerated dose of 6 µg/ml × 40 ml. The overall median survival was 8.2 months with a median survival of 5.8 months for the GBM patients. Six-month survival was 52% and 48%, respectively. Gadolinium-enhanced magnetic resonance imaging of the brain showed areas of decreased signal intensity within the tumor consistent with tumor necrosis following treatment in many patients. Conclusions: NBI-3001 appears to have an acceptable safety and toxicity profile when administered intratumorally in patients with recurrent malignant glioma.


Neurosurgery | 2007

Convection-enhanced delivery of cintredekin besudotox (interleukin-13- PE38QQR) followed by radiation therapy with and without temozolomide in newly diagnosed malignant gliomas: Phase 1 study of final safety results

Michael A. Vogelbaum; John H. Sampson; Sandeep Kunwar; Susan M. Chang; Mark E. Shaffrey; Anthony L. Asher; Frederick F. Lang; David Croteau; Kristen Parker; Amy Y. Grahn; Jeffrey W. Sherman; S. Rafat Husain; Raj K. Puri

OBJECTIVECintredekin besudotox (CB), a recombinant cytotoxin consisting of interleukin-13 and truncated Pseudomonas exotoxin, binds selectively to interleukin-13Rα2 receptors overexpressed by malignant gliomas. This study assessed the safety of CB administered by convection-enhanced delivery followed by standard external beam radiation therapy (EBRT) with or without temozolomide (Temodar; Schering-Plough, Kenilworth, NJ) in patients with newly diagnosed malignant gliomas. METHODSAfter gross total resection of the tumor, two to four intraparenchymal catheters were stereotactically placed and CB (0.25 or 0.5 μg/mL) was infused for 96 hours. This was followed, 10 to 14 days later, by EBRT (5940–6100 cGy, 5 d/wk for 6–7 wk) with or without temozolomide (75 mg/m2/d, 7 d/wk during EBRT). Safety was assessed during an 11-week observation period after catheter placement RESULTSTwenty-two patients (12 men, 10 women; median age, 55 yr; 21 with glioblastoma multiforme and one with an anaplastic mixed oligoastrocytoma) were enrolled. None of the patients experienced dose-limiting toxicities in the first two cohorts (0.25 μg/mL CB + EBRT [n = 3] and 0.25 μg/mL CB + EBRT + temozolomide [n = 3]). One patient experienced a dose-limiting toxicity (Grade 4 seizure) in the third cohort (0.5 μg/mL CB + EBRT [n = 6]). Six patients in the final cohort (0.5 μg/mL CB + EBRT + temozolomide [n = 10]) completed treatment, and one patient experienced a dose-limiting toxicity (Grade 3 aphasia and confusion). Four patients were not considered evaluable for a dose decision and were replaced. CB related adverse events occurring in more than one patient were fatigue, gait disturbance, nystagmus, and confusion. No Grade 3 to 4 hematological toxicities were observed. CONCLUSIONCB (0.5 μg/mL) administered via convection-enhanced delivery before standard radiochemotherapy seems to be well tolerated in adults with newly diagnosed malignant gliomas. Further clinical study assessment is warranted.


Neurosurgical Focus | 2013

The National Neurosurgery Quality and Outcomes Database and NeuroPoint Alliance: rationale, development, and implementation.

Anthony L. Asher; Paul C. McCormick; Nathan R. Selden; Zoher Ghogawala; Matthew J. McGirt

Patient care data will soon inform all areas of health care decision making and will define clinical performance. Organized neurosurgery believes that prospective, systematic tracking of practice patterns and patient outcomes will allow neurosurgeons to improve the quality and efficiency and, ultimately, the value of care. In support of this mission, the American Association of Neurological Surgeons, in cooperation with a broad coalition of other neurosurgical societies including the Congress of Neurological Surgeons, Society of Neurological Surgeons, and American Board of Neurological Surgery, created the NeuroPoint Alliance (NPA), a not-for-profit corporation, in 2008. The NPA coordinates a variety of national projects involving the acquisition, analysis, and reporting of clinical data from neurosurgical practice using online technologies. It was designed to meet the health care quality and related research needs of individual neurosurgeons and neurosurgical practices, national organizations, health care plans, biomedical industry, and government agencies. To meet the growing need for tools to measure and promote high-quality care, NPA collaborated with several national stakeholders to create an unprecedented program: the National Neurosurgery Quality and Outcomes Database (N(2)QOD). This resource will allow any US neurosurgeon, practice group, or hospital system to contribute to and access aggregate quality and outcomes data through a centralized, nationally coordinated clinical registry. This paper describes the practical and scientific justifications for a national neurosurgical registry; the conceptualization, design, development, and implementation of the N(2)QOD; and the likely role of prospective, cooperative clinical data collection systems in evolving systems of neurosurgical training, continuing education, research, public reporting, and maintenance of certification.


Acta neurochirurgica | 2003

Local convection enhanced delivery of IL4-Pseudomonas exotoxin (NBI-3001) for treatment of patients with recurrent malignant glioma

Friedrich Weber; Frank Floeth; Anthony L. Asher; Richard D. Bucholz; M. Berge; M. Pradoss; Susan M. Chang; J. Bruces; Walter A. Hall; N. G. Raino; Manfred Westphal; Ronald E. Warnick; Robert W. Rand; Frank Rommel; Henry Pan; Vijay N. Hingorani; Raj K. Puri

PURPOSE This was an open-label, dose-escalation trial of intratumoral administration of IL-4 Pseudomonas Exotoxin (NBI-3001) in patients with recurrent malignant glioma. PATIENTS AND METHODS A total of 31 patients with histologically verified supratentorial grade 3 and 4 astrocytoma were studied. Of these, twenty-five patients were diagnosed with glioblastoma multiforme (GBM) while six were diagnosed with anaplastic astrocytoma (AA). Patients were over 18 years of age and had Karnofsky performance scores > or = 60. Patients were assigned to one of four dose groups in a dose-escalation fashion: 6 microg/ml x 40 ml, 9 microg/ml x 40 ml, 15 microg/ml x 40 ml, or 9 microg/ml x 100 ml of NBI-3001 administered intratumorally via stereotactically placed catheters. Patients were followed with serial MRI scans and clinical assessments every four weeks for the first 16 weeks and then every eight weeks until week 26. RESULTS No drug-related systemic toxicity, as evident by lack of hematological or serum chemical changes, was apparent in any patients; treatment-related adverse effects were limited to the central nervous system. No deaths were attributable to treatment. Drug-related Grade 3 or 4 toxicity was seen in 39% of patients in all dose groups and 22% of patients at the maximum tolerated dose of 6 microg/ml x 40 ml. The overall median survival was 8.2 months with a median survival of 5.8 months for the GBM patients. Six-month survival was 52% and 48%, respectively. Gadolinium-enhanced magnetic resonance imaging of the brain showed areas of decreased signal intensity within the tumor consistent with tumor necrosis following treatment in many patients. CONCLUSIONS NBI-3001 appears to have an acceptable safety and toxicity profile when administered intratumorally in patients with recurrent malignant glioma.


International Journal of Radiation Oncology Biology Physics | 2014

A New Treatment Paradigm: Neoadjuvant Radiosurgery Before Surgical Resection of Brain Metastases With Analysis of Local Tumor Recurrence

Anthony L. Asher; Stuart H. Burri; Walter F. Wiggins; Renee P Kelly; Margaret O. Boltes; H. James Norton; Robert W. Fraser

PURPOSE Resected brain metastases (BM) require radiation therapy to reduce local recurrence. Whole brain radiation therapy (WBRT) reduces recurrence, but with potential toxicity. Postoperative stereotactic radiosurgery (SRS) is a strategy without prospective data and problematic target delineation. SRS delivered in the preoperative setting (neoadjuvant, or NaSRS) allows clear target definition and reduction of intraoperative dissemination of tumor cells. METHODS AND MATERIALS Our treatment of resectable BM with NaSRS was begun in 2005. Subsequently, a prospective trial of NaSRS was undertaken. A total of 47 consecutively treated patients (23 database and 24 prospective trial) with a total of 51 lesions were reviewed. No statistical difference was observed between the 2 cohorts, and they were combined for analysis. The median follow-up time was 12 months (range, 1-58 months), and the median age was 57. A median of 1 day elapsed between NaSRS and resection. The median diameter of lesions was 3.04 cm (range, 1.34-5.21 cm), and the median volume was 8.49 cc (range, 0.89-46.7 cc). A dose reduction strategy was used, with a median dose of 14 Gy (range, 11.6-18 Gy) prescribed to 80% isodose. RESULTS Kaplan-Meier overall survival was 77.8% and 60.0% at 6 and 12 months. Kaplan-Meier local control was 97.8%, 85.6%, and 71.8% at 6, 12, and 24 months, respectively. Five of 8 failures were proved pathologically without radiation necrosis. There were no perioperative adverse events. Ultimately, 14.8% of the patients were treated with WBRT. Local failure was more likely with lesions >10 cc (P=.01), >3.4 cm (P=.014), with a trend in surface lesions (P=.066) and eloquent areas (P=.052). Six of the 8 failures had an obvious dural attachment or proximity to draining veins. CONCLUSIONS NaSRS can be performed safely and effectively with excellent results without documented radiation necrosis. Local control was excellent even in the setting of large (>3 cm) lesions. The strong majority of patients were able to avoid WBRT. NaSRS merits consideration in a multi-institution trial.


Neurosurgery | 2006

Self-assessment in Neurological Surgery: The SANS Wired White Paper

Brian T. Ragel; Anthony L. Asher; Nathan R. Selden; Joel D. MacDonald

OBJECTIVE:Periodic self-assessment is an important component of postgraduate medical education and certification. The Self-assessment in Neurological Surgery (SANS) examination has a history of usefulness for neurosurgical written and oral board examination preparation. The SANS Wired test represents a recreation of the original SANS test using an Internet-based platform. Advanced functionality and contemporary content have been added to meet the increasing requirements for demonstration of lifelong learning and self-assessment as part of the Maintenance of Certification (MOC) process. METHODS:A needs assessment was performed before the development of SANS Wired. Postexamination surveys for users obtaining continuing medical education credit were analyzed for user satisfaction with the platform and content. Test-item performance metrics were analyzed based on first-attempt responses. The economic value of SANS Wired as a component of the mandatory MOC process was evaluated. RESULTS:The needs assessment identified a deficiency of available content and mechanisms for neurosurgery-specific self-assessment. As of October 15, 2005, a total of 588 individuals had subscribed to SANS Wired (28 institutional licenses accounted for 229 users). Eighty-eight post-test surveys were analyzed for user satisfaction. Ninety-four percent of responses indicated that learning objectives had been met. Initial performance metrics show an average point-biserial discrimination index of +0.18 for all test items. CONCLUSION:The SANS Wired system seems to be an effective platform for neurosurgical self-assessment and is acceptable to users. The system satisfies, in part, two of the four required components of MOC, namely, periodic self-assessment and demonstration of cognitive expertise. It is endorsed by the American Board of Neurological Surgeons for MOC.


Neurosurgery Clinics of North America | 2015

Using Clinical Registries to Improve the Quality of Neurosurgical Care

Anthony L. Asher; Scott L. Parker; John D. Rolston; Nathan R. Selden; Matthew J. McGirt

Despite rising and unsustainable US health care costs, many stakeholders feel that the quality of medical services is limited and inconsistent. Value-based reforms are touted as the key to achieving health care system sustainability. Health care value is defined as quality delivered divided by cost incurred. Unfortunately, quality in health care is difficult to accurately define and methods to reliably assess and report health care quality are often lacking. Clinical registries have emerged as important mechanisms to define, measure, and promote health care quality. The purpose of this article is to describe the role of registries in neurosurgical quality improvement.


Neurosurgical Focus | 2013

The future of practice science: challenges and opportunities for neurosurgery

Nathan R. Selden; Zoher Ghogawala; Robert E. Harbaugh; Zachary Litvack; Matthew J. McGirt; Anthony L. Asher

Outcomes-directed approaches to quality improvement have been adopted by diverse industries and are increasingly the focus of government-mandated reforms to health care education and delivery. The authors identify and review current reform initiatives originating from agencies regulating and funding graduate medical education and health care delivery. These reforms use outcomes-based methodologies and incorporate principles of lifelong learning and patient centeredness. Important new initiatives include the Accreditation Council for Graduate Medical Education Milestones; the pending adoption by the American Board of Neurological Surgery of new requirements for Maintenance of Certification that are in part outcomes based; initiation by health care systems and consortia of public reporting of patient outcomes data; institution by the Centers for Medicare & Medicaid Services of requirements for comparative effectiveness research and the physician quality reporting system; and linking of health care reimbursement in part to patient outcomes data and quality measures. Opportunities exist to coordinate and unify patient outcomes measurement throughout neurosurgical training and practice, enabling effective patient-centered improvements in care delivery as well as efficient compliance with regulatory mandates. Coordination will likely require the development of a new science of practice based in the daily clinical environment and utilizing clinical data registries. A generation of outcomes science and quality experts within neurosurgery should be trained to facilitate attainment of these goals.

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Stuart H. Burri

Carolinas Healthcare System

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Roshan S. Prabhu

Carolinas Healthcare System

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Clinton J. Devin

Vanderbilt University Medical Center

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Matthew J. McGirt

Carolinas Healthcare System

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Ashley L. Sumrall

Carolinas Healthcare System

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Benjamin J. Moeller

University of Texas MD Anderson Cancer Center

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