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Lung Cancer Screening (PDQ®)     
Last Modified: 10/30/2008
Health Professional Version
Summary of Evidence

Screening for Lung Cancer with Chest X-Ray and/or Sputum Cytology
        Benefits
        Harms
Screening for Lung Cancer with Low-Dose Helical Computed Tomography (LDCT)
        Benefits
        Harms

Separate PDQ summaries on Lung Cancer Prevention 1, Small Cell Lung Cancer Treatment 2, Non-Small Cell Lung Cancer Treatment 3, and Levels of Evidence for Cancer Screening and Prevention Studies 4 are also available.

Screening for Lung Cancer with Chest X-Ray and/or Sputum Cytology

Benefits

Based on fair evidence, screening does not reduce mortality from lung cancer.

Description of the Evidence

  • Study Design: Evidence obtained from randomized controlled trials.
  • Internal Validity: Fair, due to lack of unscreened groups and contamination.
  • Consistency: Good.
  • Direction and Magnitude of Effect: No evidence of effect.
  • External Validity: Fair, due to lack of women and minority groups.
Harms

Based on solid evidence, screening would lead to false-positive tests and unnecessary invasive diagnostic procedures and treatments.

Description of the Evidence

  • Study Design: Evidence obtained from randomized controlled trials.
  • Internal Validity: Fair.
  • Consistency: Good.
  • Direction and Magnitude of Effect: False-positive results range from 4% to 15%; there is a possibility of overdiagnosis and overtreatment (magnitude uncertain).
  • External Validity: Fair.
Screening for Lung Cancer with Low-Dose Helical Computed Tomography (LDCT)

Benefits

The evidence is inadequate to determine whether screening reduces mortality from lung cancer.

Description of the Evidence

  • Study Design: Evidence obtained from cohort or case-control studies.
  • Internal Validity: Poor for answering the question of mortality reduction from screening with LDCT.
  • Consistency: Good.
  • Direction and Magnitude of Effect: Cannot determine from the available studies.
  • External Validity: Not applicable; the internal validity of the evidence is poor.
Harms

Based on solid evidence, screening would lead to false-positive tests and unnecessary invasive diagnostic procedures and treatments.

Description of the Evidence

  • Study Design: Evidence obtained from cohort or case-control studies.
  • Internal Validity: Poor.
  • Consistency: Good.
  • Direction and Magnitude of Effect: False-positive results range from 20% to 50%; overdiagnosis and overtreatment are possible (magnitude uncertain).
  • External Validity: Fair.


Table of Links

1http://www.cancer.gov/cancertopics/pdq/prevention/lung/HealthProfessional
2http://www.cancer.gov/cancertopics/pdq/treatment/small-cell-lung/healthprofessi
onal
3http://www.cancer.gov/cancertopics/pdq/treatment/non-small-cell-lung/HealthProf
essional
4http://www.cancer.gov/cancertopics/pdq/screening/levels-of-evidence/HealthProfe
ssional