title: Prognostic factors in primary nonmetastatic Ewing sarcoma of the rib in children and young adults.
abstract: BACKGROUND
  The rarity of Ewing sarcoma of rib has resulted in paucity of data, particularly on the prognostic factors and pattern of relapses. We analyzed the recurrences in patients with primary nonmetastatic Ewing sarcoma of the rib and examined prognostic factors of poor outcome.
  
  
  METHODS
  From January 2004 to January 2011, 37 patients were treated. After induction chemotherapy, complete (from costal cartilage to vertebra) or partial excision of involved rib with or without adjacent ribs was performed. Postoperative radiotherapy was administered for positive margins, poor response to chemotherapy, and large primary tumors with significant soft tissue component at presentation.
  
  
  RESULTS
  Disease relapsed in 16 patients: at the local site (n = 5), both local and distant (n = 2), and distant site only (n = 9). The projected 5-year cause-specific, relapse-free survival and local control were 50%, 44%, and 72%. Poor response to chemotherapy (>5% residual tumor) and resection of adjacent lung parenchyma (a surrogate for tumor extension) were adverse prognostic factors for relapse-free survival in multivariate analysis.
  
  
  CONCLUSIONS
  Relapses occurred more often at distant sites and had a poor outcome. In this study, poor histologic response to chemotherapy (P = .04) and the infiltration of adjacent lung parenchyma (P = .01) are adverse prognostic factors.
authors.affiliation: Division of Pediatric Surgical Oncology, Department of Surgical Oncology, Tata Memorial Centre, Parel. 400012, Bombay, India. sajidshafiques@hotmail.com
authors.forename: Sajid S
authors.initials: SS
authors.lastname: Qureshi
authors.forename: Seema
authors.initials: S
authors.lastname: Kembhavi
authors.forename: Tushar
authors.initials: T
authors.lastname: Vora
authors.forename: Mukta
authors.initials: M
authors.lastname: Ramadwar
authors.forename: Siddharth
authors.initials: S
authors.lastname: Laskar
authors.forename: Sanjay
authors.initials: S
authors.lastname: Talole
authors.forename: Purna
authors.initials: P
authors.lastname: Kurkure
mesh_terms: D000293:Adolescent; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D049268:Positron-Emission Tomography; D011379:Prognosis; D016016:Proportional Hazards Models; D011879:Radiotherapy Dosage; D012272:Ribs / Q000473:pathology*; D012307:Risk Factors; D012512:Sarcoma, Ewing / Q000175:diagnosis / Q000473:pathology* / Q000628:therapy*; D015996:Survival Rate; D013908:Thoracotomy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult