The quality of radiation therapy (RT) treatment plans directly affects the outcomes of clinical trials. KBP solutions have been utilized in RT plan quality assurance (QA). In this study, we evaluated the quality of RT plans for brain and head/neck cancers enrolled in multi-institutional clinical trials utilizing a KBP approach.
View Article and Find Full Text PDFBackground: Standard treatment for locally advanced cervical cancer is chemoradiotherapy, but many patients relapse and die of metastatic disease. We aimed to determine the effects on survival of adjuvant chemotherapy after chemoradiotherapy.
Methods: The OUTBACK trial was a multicentre, open-label, randomised, phase 3 trial done in 157 hospitals in Australia, China, Canada, New Zealand, Saudi Arabia, Singapore, and the USA.
Background: Three- and five-year progression-free survival (PFS) for low-risk meningioma managed with surgery and observation reportedly exceeds 90%. Herewith we summarize outcomes for low-risk meningioma patients enrolled on NRG/RTOG 0539.
Methods: This phase II trial allocated patients to one of three groups per World Health Organization grade, recurrence status, and resection extent.
Introduction: The ZAP-X Gyroscopic Radiosurgery system (ZAP Surgical Systems, Inc., San Carlos, CA, USA) is a novel high-dose targeted stereotactic radiosurgery platform for outpatient use that includes self-shielding, X-ray image guidance, and the capacity to aim the radiation beam gyroscopically at an intracranial lesion using 5 independent degrees of freedom. The ZAP-X Gyroscopic Radiosurgery system accomplishes these actions while meeting widely accepted standards for dose gradient and accuracy.
View Article and Find Full Text PDFPurpose: This study reports a single-institution experience with beam data acquisition and film-based validation for a novel self-shielded sterotactic radiosurgery unit and investigates detector dependency on field output factors (OFs), off-axis ratios (OARs), and percent depth dose (PDD) measurements within the context of small-field dosimetry.
Methods: The delivery platform for this unit consists of a 2.7-MV S-band linear accelerator mounted on coupled gimbals that rotate around a common isocenter (source-to-axis distance [SAD] = 450 mm), allowing for more than 260 noncoplanar beam angles.
Purpose: To evaluate the treatment planning system (TPS) performance of the ZAP-X stereotactic radiosurgery (SRS) system through nondosimetric, dosimetric, and end-to-end (E2E) tests.
Methods: A comprehensive set of TPS commissioning and validation tests was developed using published guidelines. Nondosimetric validation tests included information transfer, computed tomography-magnetic resonance (CT-MR) image registration, structure/contouring, geometry, dose tools, and CT density.
Purpose: To establish the maximum tolerated dose of a 3-fraction hypofractionated stereotactic reirradiation schedule when delivered with concomitant bevacizumab to treat recurrent high-grade gliomas.
Methods And Materials: Patients with recurrent high-grade glioma with Karnofsky performance status ≥60, history of standard fractionated initial radiation, tumor volume at recurrence ≤40 cm, and absence of brainstem or corpus callosum involvement were eligible. A standard 3+3 phase 1 dose escalation trial design was utilized, with dose-limiting toxicities defined as any grade 3 to 5 toxicities possibly, probably, or definitely related to radiation.
Background: As radiation has become an increasingly popular primary treatment option for sporadic vestibular schwannomas, there is a minority of tumors that do not respond favorably to radiation. Data on repeat radiosurgery are emerging, and salvage surgery has been associated with increased technical difficulty and poor facial nerve outcomes.
Objective: To review the current literature and report our results with surgical resection of sporadic vestibular schwannomas that have failed primary radiation treatment.
Objective: To evaluate the efficacy and toxicity of fractionated stereotactic radiotherapy (FSRT) for chordoma and chondrosarcoma.
Methods: Twenty consecutive patients with a histopathologic diagnosis of chordoma ( = 16) or chondrosarcoma ( = 4) treated between 2010 and 2016 were retrospectively identified. All patients underwent FSRT in five fractions to a median dose of 37.
OBJECTIVE Although postoperative stereotactic body radiation therapy (SBRT) for spinal metastases is increasingly performed, few guidelines exist for this application. The purpose of this study is to develop consensus guidelines to promote safe and effective treatment for patients with spinal metastases. METHODS Fifteen radiation oncologists and 5 neurosurgeons, representing 19 centers in 4 countries and having a collective experience of more than 1300 postoperative spine SBRT cases, completed a 19-question survey about postoperative spine SBRT practice.
View Article and Find Full Text PDFWhile immunotherapy may offer promising new approaches for high grade meningiomas, little is currently known of the immune landscape in meningiomas. We sought to characterize the immune microenvironment and a potentially targetable antigen mesothelin across WHO grade I-III cases of meningiomas, and how infiltrating immune populations relate to patient outcomes. Immunohistochemistry was performed on tissue microarrays constructed from 96 meningioma cases.
View Article and Find Full Text PDFPurpose/objectives: Whole-brain radiation for brain metastases can result in cognitive side effects. Hippocampal-sparing techniques have been developed to decrease morbidity, but they carry the risk of underdosing lesions near the hippocampus due to the unavoidable dose gradient from the hippocampal surface to the prescription isodose surface. This study examines the impact of variable levels of hippocampal sparing on the underdosing of potential brain metastases.
View Article and Find Full Text PDFOBJECTIVE High-resolution double-dose gadolinium-enhanced Gamma Knife (GK) radiosurgery-planning MRI (GK MRI) on the day of GK treatment can detect additional brain metastases undiagnosed on the prior diagnostic MRI scan (dMRI), revealing increased intracranial disease burden on the day of radiosurgery, and potentially necessitating a reevaluation of appropriate management. The authors identified factors associated with detecting additional metastases on GK MRI and investigated the relationship between detection of additional metastases and postradiosurgery patient outcomes. METHODS The authors identified 326 patients who received GK radiosurgery at their institution from 2010 through 2013 and had a prior dMRI available for comparison of numbers of brain metastases.
View Article and Find Full Text PDFA clinical workflow was developed for urgent palliative radiotherapy treatments that integrates patient simulation, planning, quality assurance, and treatment in one 30-minute session. This has been successfully tested and implemented clinically on a linac with MV CBCT capabilities. To make this approach available to all clin-ics equipped with common imaging systems, dose calculation accuracy based on treatment sites was assessed for other imaging units.
View Article and Find Full Text PDFRadiotherapy (RT) of the brain is associated with significant stigma in the neuro-oncology community. This is primarily because of the potentially severe complications with which it may be associated. These complications, especially in subacute and latent settings, are often unpredictable, potentially progressive, and irreversible.
View Article and Find Full Text PDFThe behavior of rhabdoid meningiomas otherwise lacking malignant features remains unknown as most of the originally reported aggressive cases showed anaplastic histologic features independently of rhabdoid phenotype. We studied 44 patients with rhabdoid meningiomas lacking anaplastic features. Median age at diagnosis was 48.
View Article and Find Full Text PDFBackground: With advances in the understanding of histopathology on outcome, accurate meningioma grading becomes critical and drives treatment selection. The 2000 and 2007 WHO schema greatly increased the proportion of grade II meningiomas. Although associations with progression-free survival (PFS) and overall survival (OS) have been independently validated, interobserver concordance has not been formally assessed.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
September 2015
Purpose: The purpose of this study was to evaluate workflow and patient outcomes related to frameless stereotactic radiation surgery (SRS) for brain metastases.
Methods And Materials: We reviewed all treatment demographics, clinical outcomes, and workflow timing, including time from magnetic resonance imaging (MRI), computed tomography (CT) simulation, insurance authorization, and consultation to the start of SRS for brain metastases.
Results: A total of 82 patients with 151 brain metastases treated with SRS were evaluated.
Object: Vestibular schwannomas (VSs) are managed in 3 ways: observation ("wait and scan"); Gamma Knife surgery (GKS); or microsurgery. Whereas there is considerable literature regarding which management approach is superior, there are only a few studies addressing the cost of treating VSs, and there are no cost-utility analyses in the US to date.
Methods: In this study, the authors used the University of California at San Francisco medical record and hospital accounting databases to determine total hospital charges and costs for 33 patients who underwent open surgery, 42 patients who had GKS, and 12 patients who were observed between 2010 and 2013.
Stereotactic radiosurgery provides conformal treatment of intracranial lesions, but when multiple lesions are treated, cumulative dose to structures such as the hippocampi may be increased. We analyzed hippocampal dose for patients treated with radiosurgery for multiple brain metastases. We then investigated a means to minimize hippocampal dose.
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