For patients with confirmed Ewing sarcoma, pretreatment staging studies should include magnetic resonance imaging (MRI) and/or computed tomography (CT) scan, depending on the primary site. Despite the fact that CT and MRI are both equivalent in terms of staging, use of both imaging modalities may help radiation therapy planning. Whole-body MRI may provide additional information that could potentially alter therapy planning. Additional pretreatment staging studies should include bone scan, CT scan of the chest, and bone marrow aspiration and biopsy. A staging modality under evaluation but not required on current clinical trials is molecular analysis of bone marrow for the presence of fusion transcript. In certain studies, determination of pretreatment tumor volume is an important variable.
Although positron emission tomography using fluorodeoxyglucose (FDG-PET) or FDG-PET/CT are optional staging modalities, they have demonstrated high sensitivity and specificity in Ewing sarcoma and may provide additional information that alters therapy planning. In one institutional study, FDG-PET had a very high correlation with bone scan; the investigators suggested that it could replace bone scan for the initial extent of disease evaluation. This finding was confirmed in a single-institution retrospective review. FDG-PET/CT is more accurate than FDG-PET alone in Ewing sarcoma.[5,6,7]
Childhood astrocytoma is a disease in which benign (noncancer) or malignant (cancer) cells form in the tissues of the brain.
Astrocytomas are tumors that start in star-shaped brain cells called astrocytes. An astrocyte is a type of glial cell. Glial cells hold nerve cells in place, bring food and oxygen to them, and help protect them from disease, such as infection. Gliomas are tumors that form from glial cells. An astrocytoma is a type of glioma.
Astrocytoma is the most common type of glioma...
For Ewing sarcoma, the tumor is defined as localized when, by clinical and imaging techniques, there is no spread beyond the primary site or regional lymph node involvement. Continuous extension into adjacent soft tissue may occur. If there is a question of regional lymph node involvement, an excisional biopsy should be performed.
Meyer JS, Nadel HR, Marina N, et al.: Imaging guidelines for children with Ewing sarcoma and osteosarcoma: a report from the Children's Oncology Group Bone Tumor Committee. Pediatr Blood Cancer 51 (2): 163-70, 2008.
Mentzel HJ, Kentouche K, Sauner D, et al.: Comparison of whole-body STIR-MRI and 99mTc-methylene-diphosphonate scintigraphy in children with suspected multifocal bone lesions. Eur Radiol 14 (12): 2297-302, 2004.
Newman EN, Jones RL, Hawkins DS: An evaluation of [F-18]-fluorodeoxy-D-glucose positron emission tomography, bone scan, and bone marrow aspiration/biopsy as staging investigations in Ewing sarcoma. Pediatr Blood Cancer 60 (7): 1113-7, 2013.
Ulaner GA, Magnan H, Healey JH, et al.: Is methylene diphosphonate bone scan necessary for initial staging of Ewing sarcoma if 18F-FDG PET/CT is performed? AJR Am J Roentgenol 202 (4): 859-67, 2014.
Völker T, Denecke T, Steffen I, et al.: Positron emission tomography for staging of pediatric sarcoma patients: results of a prospective multicenter trial. J Clin Oncol 25 (34): 5435-41, 2007.
Gerth HU, Juergens KU, Dirksen U, et al.: Significant benefit of multimodal imaging: PET/CT compared with PET alone in staging and follow-up of patients with Ewing tumors. J Nucl Med 48 (12): 1932-9, 2007.
Treglia G, Salsano M, Stefanelli A, et al.: Diagnostic accuracy of ¹⁸F-FDG-PET and PET/CT in patients with Ewing sarcoma family tumours: a systematic review and a meta-analysis. Skeletal Radiol 41 (3): 249-56, 2012.
In this article
This information is produced and provided by the National
Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National
Institute via the Internet web site at http://
.gov or call 1-800-4-CANCER.
WebMD Public Information from the National Cancer Institute
This information is not intended to replace the advice of a doctor.
Healthwise disclaims any liability for the decisions you make based on this