title: Local Control With 21-Gy Radiation Therapy for High-Risk Neuroblastoma.
abstract: To evaluate local control after 21-Gy radiation therapy (RT) to the primary site in patients with high-risk neuroblastoma.
  
  
  
  After receiving dose-intensive chemotherapy and gross total resection (GTR), 246 patients (aged 1.2-17.9 years, median 4.0 years) with high-risk neuroblastoma underwent RT to the primary site at Memorial Sloan Kettering from 2000 to 2014. Radiation therapy consisted of 21 Gy in twice-daily fractions of 1.5 Gy each. Local failure (LF) was correlated with biologic prognostic factors and clinical findings at the time of diagnosis and start of RT.
  
  
  
  Median follow-up of surviving patients was 6.4 years. Cumulative incidence of LF was 7.1% at 2 years after RT and 9.8% at 5 years after RT. The isolated LF rate was 3.0%. Eighty-six percent of all local failures were within the RT field. Local control was worse in patients who required more than 1 surgical resection to achieve GTR (22.4% vs 8.3%, P=.01). There was also a trend toward inferior local control with MYCN-amplified tumors or serum lactate dehydrogenase ≥1500 U/L (P=.09 and P=.06, respectively).
  
  
  
  After intensive chemotherapy and maximal surgical debulking, hyperfractionated RT with 21 Gy in high-risk neuroblastoma results in excellent local control. Given the young patient age, concern for late effects, and local control >90%, dose reduction may be appropriate for patients without MYCN amplification who achieve GTR.
authors.affiliation: Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Dana L
authors.initials: DL
authors.lastname: Casey
authors.affiliation: Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Brian H
authors.initials: BH
authors.lastname: Kushner
authors.affiliation: Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Nai-Kong V
authors.initials: NK
authors.lastname: Cheung
authors.affiliation: Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Shakeel
authors.initials: S
authors.lastname: Modak
authors.affiliation: Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Michael P
authors.initials: MP
authors.lastname: LaQuaglia
authors.affiliation: Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York. Electronic address: woldens@mskcc.org.
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Wolden
mesh_terms: D000293:Adolescent; D015984:Causality; D059248:Chemoradiotherapy / Q000401:mortality*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D015897:Comorbidity; D018572:Disease-Free Survival; D019583:Dose Fractionation, Radiation; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000401:mortality* / Q000517:prevention & control; D009447:Neuroblastoma / Q000401:mortality* / Q000628:therapy*; D009518:New York / Q000453:epidemiology; D011832:Radiation Injuries / Q000401:mortality* / Q000517:prevention & control; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate