RESUMO
BACKGROUND AND PURPOSE: HERBY was a Phase II multicenter trial setup to establish the efficacy and safety of adding bevacizumab to radiation therapy and temozolomide in pediatric patients with newly diagnosed non-brain stem high-grade gliomas. This study evaluates the implementation of the radiologic aspects of HERBY. MATERIALS AND METHODS: We analyzed multimodal imaging compliance rates and scan quality for participating sites, adjudication rates and reading times for the central review process, the influence of different Response Assessment in Neuro-Oncology criteria in the final response, the incidence of pseudoprogression, and the benefit of incorporating multimodal imaging into the decision process. RESULTS: Multimodal imaging compliance rates were the following: diffusion, 82%; perfusion, 60%; and spectroscopy, 48%. Neuroradiologists' responses differed for 50% of scans, requiring adjudication, with a total average reading time per patient of approximately 3 hours. Pseudoprogression occurred in 10/116 (9%) cases, 8 in the radiation therapy/temozolomide arm and 2 in the bevacizumab arm (P < .01). Increased target enhancing lesion diameter was a reason for progression in 8/86 cases (9.3%) but never the only radiologic or clinical reason. Event-free survival was predicted earlier in 5/86 (5.8%) patients by multimodal imaging (diffusion, n = 4; perfusion, n = 1). CONCLUSIONS: The addition of multimodal imaging to the response criteria modified the assessment in a small number of cases, determining progression earlier than structural imaging alone. Increased target lesion diameter, accounting for a large proportion of reading time, was never the only reason to designate disease progression.
Assuntos
Neoplasias do Tronco Encefálico/diagnóstico por imagem , Ensaios Clínicos Fase II como Assunto , Glioma/diagnóstico por imagem , Imagem Multimodal , Neuroimagem , Bevacizumab/uso terapêutico , Neoplasias do Tronco Encefálico/patologia , Neoplasias do Tronco Encefálico/terapia , Quimiorradioterapia/métodos , Criança , Ensaios Clínicos Fase II como Assunto/métodos , Progressão da Doença , Intervalo Livre de Doença , Feminino , Glioma/patologia , Glioma/terapia , Humanos , Masculino , Estudos Multicêntricos como Assunto/métodos , Imagem Multimodal/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Temozolomida/uso terapêuticoRESUMO
Determination of tumor response to treatment in neuro-oncology is challenging, particularly when antiangiogenic agents are considered. Nontumoral factors (eg, blood-brain barrier disruption, edema, and necrosis) can alter contrast enhancement independent of true tumor response/progression. Furthermore, gliomas are often infiltrative, with nonenhancing components. In adults, the Response Assessment in Neuro-Oncology (RANO) criteria attempted to address these issues. No such guidelines exist yet for children. The ongoing randomized phase II trial, A Study of Avastin (bevacizumab) in Combination With Temolozomide (TMZ) and Radiotherapy in Paediatric and Adolescent Patients With High-Grade Glioma (HERBY), will establish the efficacy and safety of the antiangiogenic agent bevacizumab for the first-line treatment of newly diagnosed high-grade glioma in children (n = 121 patients, enrollment complete). The primary end point is event-free survival (tumor progression/recurrence by central review, second primary malignancy, or death). Determination of progression or response is based on predefined clinical and radiographic criteria, modeled on the RANO criteria and supported by expert pseudoprogression review and the use of standardized imaging protocols. The HERBY trial will also compare conventional MR imaging (T1-weighted and T2/fluid-attenuated inversion recovery sequences) with conventional MR imaging plus diffusion/perfusion imaging for response assessment. It is anticipated that HERBY will provide new insights into antiangiogenic-treated pediatric brain tumors. HERBY will also investigate the practicality of obtaining adequate quality diffusion/perfusion scans in a trial setting, and the feasibility of implementing standard imaging protocols across multiple sites. To date, 61/73 (83.6%) patients with available data have completed diffusion-weighted imaging (uptake of other nonconventional techniques has been limited). Harmonization of imaging protocols and techniques may improve the robustness of pediatric neuro-oncology studies and aid future trial comparability.
Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Adolescente , Adulto , Inibidores da Angiogênese/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Criança , Progressão da Doença , Intervalo Livre de Doença , Feminino , Glioma/tratamento farmacológico , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética , MasculinoRESUMO
The role of magnetic resonance imaging in the assessment of giant intracranial aneurysms was compared with angiography and contrast-enhanced computed tomography (CT) in 18 patients. The use of T1- and T2-weighted spin-echo (SE) sequences demonstrated both the presence and the evolution of thrombus within these lesions. High-velocity flow within the parent vessels and still-patent lumen could be defined as an area of absent signal. The use of even-echo rephasing (EER) sequences provided a rapid technique for demonstrating and confirming the presence of luminal flow, which is shown as areas of high signal. The combination of SE and EER techniques proved superior to CT in the assessment of thrombus and flow patterns in these lesions, as well as enabling superior demonstration of the patency of the parent vessel following surgical ligation. Computed tomography remains the most accurate method of defining the presence and location of associated calcification.