title: Computed tomography for pulmonary embolism: assessment of a 1-year cohort and estimated cancer risk associated with diagnostic irradiation.
abstract: BACKGROUND
  The principal concern of any radiation exposure in computed tomography (CT) is the induction of stochastic risks of developing a radiation-induced cancer. The results given in this manuscript will allow to (re-)calculate yield of chest CT.
  
  
  OBJECTIVE
  To demonstrate a method to evaluate the lifetime attributable risk (LAR) of cancer incidence/mortality due to a single diagnostic investigation in a 1-year cohort of consecutive chest CT for suspected pulmonary embolism (PE).
  
  
  METHODS
  A 1-year cohort of consecutive chest CT for suspected PE using a standard scan protocol was analyzed retrospectively (691 patients, 352 men, 339 women). Normalized patient-specific estimations of the radiation doses received by individual organs were correlated with age- and sex-specific mean predicted cancer incidence and age- and sex-specific predicted cancer mortality based on the BEIR VII results. Additional correlation was provided for natural occurring risks.
  
  
  RESULTS
  LAR of cancer incidence/mortality following one chest CT was calculated for cancer of the stomach, colon, liver, lung, breast, uterus, ovaries, bladder, thyroid, and for leukemia. LAR remains very low for all age and sex categories, being highest for cancer of the lungs and breasts in 20-year-old women (0.61% and 0.4%, respectively). Summation of all cancer sites analyzed raised the cumulative relative LAR up to 2.76% in 20-year-old women.
  
  
  CONCLUSIONS
  Using the method presented in this work, LAR of cancer incidence and cancer mortality for a single chest CT for PE seems very low for all age groups and both sexes, but being highest for young patients. Hence the risk for radiation-induced organ cancers must be outweighed with the potential benefit or a treatment and the potential risks of a missed and therefore untreated PE.
authors.affiliation: Department of Radiology and Nuclear Medicine, University Hospital, Basel, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Niemann
authors.forename: I
authors.initials: I
authors.lastname: Zbinden
authors.forename: H W
authors.initials: HW
authors.lastname: Roser
authors.forename: J
authors.initials: J
authors.lastname: Bremerich
authors.forename: M
authors.initials: M
authors.lastname: Remy-Jardin
authors.forename: G
authors.initials: G
authors.lastname: Bongartz
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology* / Q000401:mortality; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D011829:Radiation Dosage; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D014057:Tomography, X-Ray Computed / Q000009:adverse effects*
keywords: Risk assessment; epidemiology; pulmonary embolism; spiral computed; tomography