title: Imaging Features of Primary Tumors and Metastatic Patterns of the Extraskeletal Ewing Sarcoma Family of Tumors in Adults: A 17-Year Experience at a Single Institution.
abstract: OBJECTIVE
  To comprehensively analyze the spectrum of imaging features of the primary tumors and metastatic patterns of the Extraskeletal Ewing sarcoma family of tumors (EES) in adults.
  
  
  METHODS
  We performed a computerized search of our hospital's data-warehouse from 1996 to 2013 using codes for Ewing sarcoma and primitive neuroectodermal tumors as well as the demographic code for ≥ 18 years of age. We selected subjects who were histologically confirmed to have Ewing sarcoma of extraskeletal origin. Imaging features of the primary tumor and metastatic disease were evaluated for lesion location, size, enhancement pattern, necrosis, margin, and invasion of adjacent organs.
  
  
  RESULTS
  Among the 70 patients (mean age, 35.8 ± 15.6 years; range, 18-67 years) included in our study, primary tumors of EES occurred in the soft tissue and extremities (n = 20), abdomen and pelvis (n = 18), thorax (n = 14), paravertebral space (n = 8), head and neck (n = 6), and an unknown primary site (n = 4). Most primary tumors manifested as large and bulky soft-tissue masses (mean size, 9.0 cm; range, 1.3-23.0 cm), frequently invading adjacent organs (45.6%) and showed heterogeneous enhancement (73.7%), a well-defined (66.7%) margin, and partial necrosis/cystic degeneration (81.9%). Notably, 29 patients had metastatic disease detected at their initial diagnosis. The most frequent site of metastasis was lymph nodes (75.9%), followed by bone (31.0%), lung (20.7%), abdominal solid organs (13.8%), peritoneum (13.8%), pleura (6.9%), and brain (3.4%).
  
  
  CONCLUSIONS
  Primary tumors of EES can occur anywhere and mostly manifest as large and bulky, soft-tissue masses. Lymph nodes are the most frequent metastasis sites.
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Jimi
authors.initials: J
authors.lastname: Huh
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Kyung Won
authors.initials: KW
authors.lastname: Kim
authors.affiliation: Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Seong Joon
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Hyoung Jung
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Jong Seok
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul 138-736, Korea.
authors.forename: Hyun Kwon
authors.initials: HK
authors.lastname: Ha
authors.affiliation: Department of Imaging, Dana-Farber Cancer Institute, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Sree Harsha
authors.initials: SH
authors.lastname: Tirumani
authors.affiliation: Department of Imaging, Dana-Farber Cancer Institute, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Nikhil H
authors.initials: NH
authors.lastname: Ramaiya
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044466:Asian People; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D018242:Neuroectodermal Tumors, Primitive / Q000000981:diagnostic imaging / Q000473:pathology; D049268:Positron-Emission Tomography; D012512:Sarcoma, Ewing / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: Computed tomography; Ewing sarcoma family of tumors; Extraskeletal Ewing sarcoma; Imaging