title: Intensity-modulated radiation therapy with dose-painting for pediatric sarcomas with pulmonary metastases.
abstract: BACKGROUND
  We examined patterns of failure in pediatric patients with thoracic sarcoma and pulmonary metastases treated with intensity-modulated radiation therapy with dose-painting (DP-IMRT).
  
  
  METHODS
  Eleven pediatric patients, five with Ewing sarcoma family tumors (ESFT) and six with rhabdomyosarcoma (RMS), with primary thoracic tumors and pulmonary metastases underwent DP-IMRT with chemotherapy for definitive treatment. Eight patients also underwent surgery. Median time to RT was 21 (15-31) weeks. Nine patients received 45-50.4-Gy in 1.8 Gy fractions to the primary tumor (n = 3) or post-operative tumor bed (n = 6). Two patients ≤4 years received 12 Gy intraoperative radiation therapy and 30.6-36 Gy IMRT postoperatively to the tumor bed. All patients received 14-16.8 Gy in 0.54-0.88 Gy fractions to the whole lungs (n = 6) or hemithorax (n = 5) using dose-painting technique. A representative case was re-planned with IMRT plus standard AP/PA whole lung irradiation (WLI) for dosimetric comparison.
  
  
  RESULTS
  With 27-month median follow-up, 3-year pulmonary relapse-free survival in all patients was 61%: 80% for RMS and 40% for ESFT. Five patients (4 ESFT and 1 RMS) experienced pulmonary relapse at median 16 (9-41) months. There were no local failures. Our representative case demonstrated more homogeneous target volume coverage of the whole lungs and decreased mean dose to esophagus (15%), heart (31%), spinal cord (15%), and liver (19%) with DP-IMRT.
  
  
  CONCLUSIONS
  The treatment of children with a primary thoracic tumor and pulmonary metastases poses a significant challenge. DP-IMRT is one solution to this technical problem. Initial data from this small series suggest DP-IMRT is feasible and produces superior sparing of critical normal tissues.
authors.affiliation: Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
authors.forename: Joanna C
authors.initials: JC
authors.lastname: Yang
authors.forename: Leonard H
authors.initials: LH
authors.lastname: Wexler
authors.forename: Paul A
authors.initials: PA
authors.lastname: Meyers
authors.forename: Laura
authors.initials: L
authors.lastname: Happersett
authors.forename: Michael P
authors.initials: MP
authors.lastname: La Quaglia
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Wolden
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy / Q000556:secondary; D008297:Male; D009362:Neoplasm Metastasis; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods; D012189:Retrospective Studies; D012208:Rhabdomyosarcoma / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy; D012512:Sarcoma, Ewing / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy; D015996:Survival Rate; D013899:Thoracic Neoplasms / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy
keywords: Ewing sarcoma family tumors; intensity-modulated radiotherapy with dose-painting; pediatric sarcomas; pulmonary metastases; rhabdomyosarcoma