title: Cancer incidence among 10,211 airline pilots: a Nordic study.
abstract: BACKGROUND
  Commercial airline pilots are exposed to cosmic radiation and other potentially carcinogenic elements during work and leisure activities.
  
  
  OBJECTIVE
  Work-related factors affect cancer pattern of the pilots.
  
  
  METHODS
  A cohort of 10,051 male and 160 female airline pilots from Denmark, Finland, Iceland, Norway, and Sweden was followed for cancer incidence through the national cancer registries. There were 177,000 person-years at follow-up, 51,000 of them accumulated after 20 yr since the time of first employment. Standardized incidence ratios (SIRs) were defined as ratios of observed over expected numbers of cases based on national cancer incidence rates. Dose-response analyses were done with Poisson regression method.
  
  
  RESULTS
  Among male pilots, there were 466 cases of cancer diagnosed vs. 456 expected. The only significantly increased SIRs concerned skin cancer: melanoma 2.3 (95% CI 1.7-3.0), squamous cell cancer 2.1 (1.7-2.8), and basal cell carcinoma 2.5 (1.9-3.2). The relative risk of skin cancers increased with the time since first employment, the number of flight hours, and the estimated radiation dose. There was an increase in the relative risk of prostate cancer with increasing number of flight hours in long-distance aircraft (p trend 0.01). No increased incidence was found for acute myeloid leukemia or brain cancer which were of interest a priori based on earlier studies.
  
  
  CONCLUSIONS
  This large study, based on reliable cancer incidence data, showed an increased incidence of skin cancer. It did not indicate a marked increase in cancer risk attributable to cosmic radiation although some influence of cosmic radiation on skin cancer cannot be entirely excluded.
authors.affiliation: Finnish Cancer Registry, Institute for Statistical and Epidemiological Cancer Research, Helsinki, Finland. eero.pukkala@cancer.fi
authors.forename: Eero
authors.initials: E
authors.lastname: Pukkala
authors.forename: Rafael
authors.initials: R
authors.lastname: Aspholm
authors.forename: Anssi
authors.initials: A
authors.lastname: Auvinen
authors.forename: Harald
authors.initials: H
authors.lastname: Eliasch
authors.forename: Maryanne
authors.initials: M
authors.lastname: Gundestrup
authors.forename: Tor
authors.initials: T
authors.lastname: Haldorsen
authors.forename: Niklas
authors.initials: N
authors.lastname: Hammar
authors.forename: Jón
authors.initials: J
authors.lastname: Hrafnkelsson
authors.forename: Pentti
authors.initials: P
authors.lastname: Kyyrönen
authors.forename: Anette
authors.initials: A
authors.lastname: Linnersjö
authors.forename: Vilhjálmur
authors.initials: V
authors.lastname: Rafnsson
authors.forename: Hans
authors.initials: H
authors.lastname: Storm
authors.forename: Ulf
authors.initials: U
authors.lastname: Tveten
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000401:Aircraft / Q000706:statistics & numerical data*; D015984:Causality; D015331:Cohort Studies; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D007055:Iceland / Q000453:epidemiology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology*; D009784:Occupational Diseases / Q000453:epidemiology*; D016273:Occupational Exposure / Q000706:statistics & numerical data; D011471:Prostatic Neoplasms / Q000453:epidemiology; D012306:Risk; D012537:Scandinavian and Nordic Countries / Q000453:epidemiology; D017678:Sex Distribution; D012878:Skin Neoplasms / Q000453:epidemiology; D016526:Workload / Q000706:statistics & numerical data