Fleischner Society pulmonary nodule recommendations

Dr Henry Knipe and Radswiki et al.

The Fleischner Society pulmonary nodule recommendations are for the follow-up and management of pulmonary nodules detected incidentally on imaging. The guideline does not apply to patients <35 years or with a history of cancer or immunosuppression. The initial guideline was released in 2005 1; subsequently, a separate guideline for the management of subsolid nodules was released in 2013 2. New revised 2017 recommendations for incidentally found solid and subsolid nodule or nodules have since been released 4.

Solitary nodule size: <6 mm

  • low-risk patients: no follow-up needed
  • high-risk patients: optional CT at 12 months (see specific scenarios below)

Solitary nodule size: 6-8 mm

  • low-risk patients: follow-up at 6-12 months, then consider further follow-up at 18-24 months
  • high-risk patients: initial follow-up CT at 6-12 months and then at 18-24 months if no change

Solitary nodule size: >8 mm

  • either low or high-risk patients
    • consider follow-up CT at 3 months, and/or CT-PET, and/or biopsy

Multiple nodules size: <6 mm

  • low-risk patients: no routine follow-up
  • high-risk patients: optional CT at 12 months

Multiple nodules size: 6-8 mm

  • low-risk patients: follow-up at 3-6 months, then consider further follow-up at 18-24 months
  • high-risk patients: follow-up at 3-6 months, then at 18-24 months if no change

Multiple nodules size: >8 mm

  • low-risk patients: follow-up at 3-6 months, then consider further follow-up at 18-24 months
  • high-risk patients: follow-up at 3-6 months, then at 18-24 months if no change

Note: newly detected indeterminate nodule in persons 35 years of age or older

  • low-risk patients: a minimal or absent history of smoking and or other known risk factors
  • high-risk patients: a history of smoking or of other known risk factors (e.g. first degree relative with lung cancer, or exposure to asbestos, radon, uranium)
  • if a nodule up to 8 mm is partly solid or is ground glass further follow-up is required after 24 months to exclude possible slow growing adenocarcinoma 
  • nodule size: <6 mm
    • no CT follow-up required
  • nodule size: ≥6 mm
    • follow up CT at 6-12 months, then every 2 years until 5 years
  • nodule size: <6 mm
    • no CT follow-up required
  • nodule size: ≥6 mm
    • follow-up CT at 3-6 months
    • if unchanged, and solid component remains <6mm, then annual follow-up for 5 years
  • nodule size: <6 mm
    • follow-up CT at 3-6 months
    • consider further follow-up at 2 and 4 years if stable
  • nodule size: ≥6 mm
    • follow-up CT at 3-6 months
    • subsequent management based on the most suspicious nodule(s)
  • ideally, the nodules should be measured on its larger diameter (regardless plane) of thin-section CT images displayed in lung windows (high–spatial-frequency filter) 5

  • thin slices (1.0–1.5 mm) should be standard for the characterisation of pulmonary nodules as it allows for a better detection of calcium or fat components and avoids volume averaging, which is commonly seen in thicker slices

  • large nodules are encouraged to be measured in both their long and short-axis for follow-up purposes 5

  • partly solid nodules that have a solid component over 3 mm should have the maximal diameter of the solid component reported 5,6
  • patients aged 35 years or younger
    • considered to have an overall low risk for malignancy pulmonary
    • in this age group, nodules are most likely to be infectious than cancer
    • management of incidentally found pulmonary nodules in this group should be individualised
  • patients with known malignancy
    • an incidentally detected pulmonary nodule is more likely to be cancer-related that in the general population
  • immunocompromised patients
    • higher risk for opportunistic pulmonary infections
  • lung cancer screening population
  • thick-slice scans (>2 mm thickness)
    • although the revised 2017 guideline does not approach this scenario, some authors advise that for nodules larger ≥6 mm, a complete thin-slice CT of the chest should be recommended as early as possible to further determine an accurate management 5
  • incomplete CT scans (e.g. abdomen and neck scans)
    • ≦8 mm nodules should follow the guideline
  • >8 mm nodules or those with very suspicious features need further complete chest CT as early as possible 4,5
  • optional 12-month follow-up for solid nodules <6 mm
    • imaging features as upper lobes location and irregularities of contour or spiculation should be considered when deciding for the follow-up 4,5

The guidelines recommend the proposed American College of Chest Physicians risk categories 4-5,7:

  • low: less than 5% estimated risk of cancer
  • intermediate: 5-65% estimated risk of cancer
  • high: > 65% estimated risk of cancer

Old guidelines have been left in place in this article in case previous reported follow-up under them.

Nodule size: ≤4 mm

  • low-risk patients: no follow-up needed
  • high-risk patients: follow-up at 12 months and if no change, no further imaging needed

Nodule size: 4-6 mm

  • low-risk patients: follow-up at 12 months and if no change, no further imaging needed
  • high-risk patients: initial follow-up CT at 6-12 months and then at 18-24 months if no change

Nodule size: >6-8 mm

  • low-risk patients: initial follow-up CT at 6-12 months and then at 18-24 months if no change
  • high-risk patients: initial follow-up CT at 3-6 months and then at 9-12 and 24 months if no change

Nodule size: >8 mm

  • either low or high-risk patients
    • follow-up CTs at around 3, 9, and 24 months
    • dynamic contrast enhanced CT, PET, and/or biopsy 

Note: newly-detected indeterminate nodule in persons 35 years of age or older.

  • low-risk patients: a minimal or absent history of smoking and or other known risk factors
  • high-risk patients: a history of smoking or other known risk factors (e.g. first degree relative with lung cancer, or exposure to asbestos, radon, uranium)
  • if a nodule up to 8 mm is partly solid or is ground glass further follow up is required after 24 months to exclude possible slow growing adenocarcinoma (BAC) 
  • nodule size ≤5 mm
    • no CT follow up required
  • nodule size >5 mm
    • follow up CT at 3 months, then annual CT for at least 3 years
  • initial follow-up CT at 3 months
  • if persistent and solid component <5 mm
    • annual CT for at least 3 years
  • if persistent and solid component ≥5 mm
    • biopsy or surgical resection
  • pure ground-glass nodules ≤5 mm
    • CT at 2 and 4 years
  • pure ground-glass nodules >5 mm, without a dominant lesion(s)
    • initial follow-up CT at 3 months then annual CT for at least 3 years
  • dominant nodule(s) with part-solid or solid component
    • initial follow-up CT at 3 months
    • if persistent, biopsy or surgical resection (especially if has >5 mm solid component)
Share article

Article information

rID: 13541
System: Chest
Section: Approach
Synonyms or Alternate Spellings:
  • Fleischner society recommonedations for pulmonary nodule assessment

Support Radiopaedia and see fewer ads

Updating… Please wait.
Loadinganimation

Alert accept

Error Unable to process the form. Check for errors and try again.

Alert accept Thank you for updating your details.