title: Risk of second malignant neoplasms after childhood leukemia and lymphoma: an international study.
abstract: BACKGROUND
  Survivors of childhood leukemia and lymphoma experience high risks of second malignant neoplasms. We quantified such risk using a large dataset from 13 population-based cancer registries.
  
  
  METHODS
  The registries provided individual data on cases of leukemia, Hodgkin lymphoma, and non-Hodgkin lymphoma occurring in children aged 0-14 years and on subsequent second malignant neoplasms for different time periods from 1943 to 2000. Risks of second malignant neoplasms were assessed through standardized incidence ratios (SIRs) and corresponding 95% confidence intervals (CIs), using the incidence rates in the general populations covered by the registries as a reference. Cumulative absolute risks were also calculated.
  
  
  RESULTS
  A total of 133 second malignant neoplasms were observed in 16,540 patients (12,731 leukemias, 1246 Hodgkin lymphomas, and 2563 non-Hodgkin lymphomas) after an average follow-up of 6.5 years. The most frequent second malignancies after leukemia were brain cancer (19 cases, SIR = 8.52, 95% CI = 5.13 to 13.3), non-Hodgkin lymphoma (nine cases, SIR = 9.41, 95% CI = 4.30 to 17.9), and thyroid cancer (nine cases, SIR = 18.8, 95% CI = 8.60 to 35.7); the most frequent after Hodgkin lymphoma were thyroid cancer (nine cases, SIR = 52.5, 95% CI = 24.0 to 99.6), breast cancer (six cases, SIR = 20.9, 95% CI = 7.66 to 45.4), and neoplasms of skin (non-melanoma) (six cases, SIR = 34.0, 95% CI = 12.5 to 74.0); and the most frequent after non-Hodgkin lymphoma were thyroid cancer (six cases, SIR = 40.4, 95% CI = 14.8 to 88.0) and brain cancer (four cases, SIR = 6.97, 95% CI = 1.90 to 17.9). Cumulative incidence of any second malignant neoplasm was 2.43% (95% CI = 1.09 to 3.78), 12.7% (95% CI = 8.29 to 17.2), and 2.50% (95% CI = 1.04 to 3.96) within 30 years from diagnosis of leukemia, Hodgkin lymphoma, and non-Hodgkin lymphoma, respectively.
  
  
  CONCLUSIONS
  This population-based study provides, to our knowledge, the most precise and up-to-date estimates for relative and absolute risks of second malignant neoplasms after childhood leukemia and lymphoma.
authors.affiliation: Childhood Cancer Registry of Piedmont, Cancer Epidemiology Unit, CPO Piemonte, CeRMS, University of Turin, Via Santena 7, 10126, Turin, Italy. milena.maule@unito.it
authors.forename: Milena
authors.initials: M
authors.lastname: Maule
authors.forename: Ghislaine
authors.initials: G
authors.lastname: Scélo
authors.forename: Guido
authors.initials: G
authors.lastname: Pastore
authors.forename: Paul
authors.initials: P
authors.lastname: Brennan
authors.forename: Kari
authors.initials: K
authors.lastname: Hemminki
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Tracey
authors.forename: Risto
authors.initials: R
authors.lastname: Sankila
authors.forename: Elisabete
authors.initials: E
authors.lastname: Weiderpass
authors.forename: Jorgen H
authors.initials: JH
authors.lastname: Olsen
authors.forename: Mary L
authors.initials: ML
authors.lastname: McBride
authors.forename: David H
authors.initials: DH
authors.lastname: Brewster
authors.forename: Vera
authors.initials: V
authors.lastname: Pompe-Kirn
authors.forename: Erich V
authors.initials: EV
authors.lastname: Kliewer
authors.forename: Kee Seng
authors.initials: KS
authors.lastname: Chia
authors.forename: Jon M
authors.initials: JM
authors.lastname: Tonita
authors.forename: Carmen
authors.initials: C
authors.lastname: Martos
authors.forename: Jon G
authors.initials: JG
authors.lastname: Jonasson
authors.forename: Franco
authors.initials: F
authors.lastname: Merletti
authors.forename: Paolo
authors.initials: P
authors.lastname: Boffetta
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007938:Leukemia / Q000473:pathology*; D008223:Lymphoma / Q000473:pathology*; D008297:Male; D016609:Neoplasms, Second Primary / Q000453:epidemiology*; D012042:Registries; D012307:Risk Factors; D017741:Survivors / Q000706:statistics & numerical data*