title: Risk of second malignancies in long-term survivors of childhood cancer.
abstract: BACKGROUND
  Childhood cancer survivors are known to be at increased risk for second malignancies.
  
  
  METHODS
  The risk of second malignancies was assessed in 1368 5-year survivors of childhood cancer treated in the Emma Children's Hospital AMC in Amsterdam. The median follow-up time was 16.8 years.
  
  
  RESULTS
  Sixty two malignancies were observed against 5.4 expected, yielding a standardised incidence ratio (SIR) of 11.2 (95% confidence interval: 8.53-14.4; absolute excess risk: 3.2 per 1000 person-years). New observations were the strongly increased risks of meningiomas (SIR=40) and basal cell carcinomas (SIR=9). Patients whose treatment involved radiotherapy had a 2-fold increased second cancer risk compared to patients with chemotherapy alone.
  
  
  CONCLUSIONS
  The relative risk of second malignancies does not decrease till at least 30 years of follow-up. With aging of the survivor cohort this results in a strong increase of the AER, due to the rising background risk of cancer with age.
authors.affiliation: Long-term follow-up clinic, Department of Paediatric Oncology, Emma Kinderziekenhuis AMC, Academic Medical Center, Post Box 22660, 1100 DD Amsterdam, The Netherlands.
authors.forename: M C
authors.initials: MC
authors.lastname: Cardous-Ubbink
authors.forename: R C
authors.initials: RC
authors.lastname: Heinen
authors.forename: P J M
authors.initials: PJ
authors.lastname: Bakker
authors.forename: H
authors.initials: H
authors.lastname: van den Berg
authors.forename: F
authors.initials: F
authors.lastname: Oldenburger
authors.forename: H N
authors.initials: HN
authors.lastname: Caron
authors.forename: P A
authors.initials: PA
authors.lastname: Voûte
authors.forename: F E
authors.initials: FE
authors.lastname: van Leeuwen
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D016609:Neoplasms, Second Primary / Q000209:etiology* / Q000401:mortality; D009426:Netherlands / Q000453:epidemiology; D012307:Risk Factors; D016019:Survival Analysis; D017741:Survivors / Q000706:statistics & numerical data*