title: Clinical features and outcomes of infants with Ewing sarcoma under 12 months of age.
abstract: BACKGROUND
  Ewing sarcoma peaks in incidence in adolescence. Infants <12 months old have rarely been reported. We aimed to compare clinical features, treatment, and survival of infants <12 months to those of older pediatric patients with Ewing sarcoma.
  
  
  METHODS
  We utilized the SEER database to identify patients <12 months of age diagnosed with Ewing sarcoma between 1973 and 2011. We used Fisher exact tests to compare clinical features and treatment modalities between these patients and patients aged 1-19 years. We used Kaplan-Meier methods to describe overall survival in these two groups.
  
  
  RESULTS
  Of 1,957 patients in the cohort, 39 (2.0%) were diagnosed at <12 months of age. Infants had a different distribution of primary tumor sites, with lower extremity tumors under represented. Compared to older patients, infants were more likely to have soft tissue tumors (81.6% vs. 27.1%; P < 0.001); have primitive neuroectodermal tumor/Askin tumor (61.5% vs. 19.9%; P < 0.001); and have tumors <8 cm (81.0% vs. 53.2%; P < 0.014). Infants were less likely to receive radiation therapy (13.2% vs. 53.3%; P < 0.001). Infants were at increased risk for early death (P < 0.013 by Wilcoxon), though long-term overall survival was not different between age groups (P < 0.25 by log rank).
  
  
  CONCLUSIONS
  Ewing sarcoma is rare in infants, with different clinical presentations and treatment approaches. These patients appear to be at higher risk for early death, but long-term survival is similar to older pediatric patients.
authors.affiliation: Department of Pediatrics, San Francisco School of Medicine, UCSF Benioff Children's Hospital, University of California, San Francisco, California.
authors.forename: Thalia
authors.initials: T
authors.lastname: Wong
authors.affiliation: Department of Pediatrics, San Francisco School of Medicine, UCSF Benioff Children's Hospital, University of California, San Francisco, California.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Goldsby
authors.affiliation: Department of Orthopedics, San Francisco School of Medicine, UCSF Benioff Children's Hospital, University of California, California.
authors.forename: Rosanna
authors.initials: R
authors.lastname: Wustrack
authors.affiliation: Department of Pediatrics, Emory University, Atlanta, Georgia.
authors.forename: Thomas
authors.initials: T
authors.lastname: Cash
authors.affiliation: Center for Cancer and Blood Disorders, Connecticut Children's Medical Center, University of Connecticut, Hartford, Connecticut.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Isakoff
authors.affiliation: Department of Pediatrics, San Francisco School of Medicine, UCSF Benioff Children's Hospital, University of California, San Francisco, California.
authors.forename: Steven G
authors.initials: SG
authors.lastname: DuBois
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D012512:Sarcoma, Ewing / Q000401:mortality* / Q000473:pathology*; D015996:Survival Rate; D014481:United States / Q000453:epidemiology
keywords: Ewing sarcoma; infants; local control; survival