title: Risk of leukemia among survivors of testicular cancer: a population-based study of 42,722 patients.
abstract: OBJECTIVE
  The aim of this study is to quantify excess absolute risk (EAR) and excess relative risk (ERR) of secondary leukemia among a large population-based group of testicular cancer survivors.
  
  
  METHODS
  We identified 42,722 1-year survivors of testicular cancer within 14 population-based cancer registries in Europe and North America (1943-2002). Poisson regression analysis was used to model EAR (per 100,000 person-years [PY]) and ERR of secondary leukemia. Cumulative risks were calculated using a competing risk model.
  
  
  RESULTS
  Secondary leukemia developed in 89 patients (EAR = 10.8 per 100,000 PY, 95% confidence interval [CI] = 7.6-14.6; ERR = 1.6, 95%CI = 1.0-2.2). Statistically significantly elevated risks were observed for acute myeloid leukemia (AML) (EAR = 7.2, 95%CI = 4.7-10.2) and acute lymphoblastic leukemia (EAR = 1.3, 95%CI = 0.4-2.8). In multivariate analyses, AML risk was higher among patients whose initial management included chemotherapy compared to those receiving radiotherapy alone (p = 0.1). Excess cumulative leukemia risk was approximately 0.23% by 30 years after testicular cancer diagnosis.
  
  
  CONCLUSIONS
  Although ERR of leukemia following testicular cancer is large, EAR and cumulative risk, which are better gauges of the population burden, are small.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA. reganho@mail.nih.gov
authors.forename: Regan
authors.initials: R
authors.lastname: Howard
authors.forename: Ethel
authors.initials: E
authors.lastname: Gilbert
authors.forename: Charles F
authors.initials: CF
authors.lastname: Lynch
authors.forename: Per
authors.initials: P
authors.lastname: Hall
authors.forename: Hans
authors.initials: H
authors.lastname: Storm
authors.forename: Eric
authors.initials: E
authors.lastname: Holowaty
authors.forename: Eero
authors.initials: E
authors.lastname: Pukkala
authors.forename: Froydis
authors.initials: F
authors.lastname: Langmark
authors.forename: Magnus
authors.initials: M
authors.lastname: Kaijser
authors.forename: Michael
authors.initials: M
authors.lastname: Andersson
authors.forename: Heikki
authors.initials: H
authors.lastname: Joensuu
authors.forename: Sophie D
authors.initials: SD
authors.lastname: Fossa
authors.forename: James M
authors.initials: JM
authors.lastname: Allan
authors.forename: Lois B
authors.initials: LB
authors.lastname: Travis
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005060:Europe / Q000453:epidemiology; D006801:Humans; D007938:Leukemia / Q000139:chemically induced* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016609:Neoplasms, Second Primary / Q000453:epidemiology*; D009656:North America / Q000453:epidemiology; D012042:Registries; D013736:Testicular Neoplasms / Q000453:epidemiology* / Q000628:therapy