RadEssentialReading-room reference
Fleischner 2017 pulmonary nodules
Flowchart · click to enlarge
For incidental nodules in adults ≥35 years. Not for lung cancer screening (use Lung-RADS), patients with known cancer, or immunocompromised patients. Size = average of long and short axes, rounded to nearest mm.
Solid nodules
| Size | Single · low risk | Single · high risk | Multiple · low risk | Multiple · high risk |
|---|---|---|---|---|
| <6 mm <100 mm³ | No routine follow-up | Optional CT at 12 mo | No routine follow-up | Optional CT at 12 mo |
| 6–8 mm 100–250 mm³ | CT 6–12 mo, then consider 18–24 mo | CT 6–12 mo, then 18–24 mo | CT 3–6 mo, then consider 18–24 mo | CT 3–6 mo, then 18–24 mo |
| >8 mm >250 mm³ | Consider CT at 3 mo, PET/CT, or tissue sampling | Consider CT at 3 mo, PET/CT, or tissue sampling | CT 3–6 mo, then consider 18–24 mo | CT 3–6 mo, then 18–24 mo |
Subsolid nodules
| Type | <6 mm | ≥6 mm |
|---|---|---|
| Single ground-glass | No routine follow-up | CT 6–12 mo to confirm persistence, then every 2 yr until 5 yr |
| Single part-solid | No routine follow-up | CT 3–6 mo to confirm persistence. If unchanged and solid component <6 mm: annual CT for 5 yr. Solid component ≥6 mm: highly suspicious |
| Multiple subsolid | CT 3–6 mo. If stable, consider CT at 2 and 4 yr | CT 3–6 mo. Manage by the most suspicious nodule |
- Single ground-glass <6 mm with suspicious morphology: consider follow-up at 2 and 4 years.
- Part-solid cannot be assigned below 6 mm. A persistent part-solid nodule with solid component ≥6 mm is highly suspicious.
- Any subsolid nodule that enlarges: consider biopsy or resection.
High-risk factors
- Heavy smoking history; asbestos, radon or uranium exposure; family history of lung cancer; older age.
- Nodule factors: spiculation, upper lobe location, emphysema or pulmonary fibrosis, multiplicity.
Pearls
- Multiple nodules: manage by the most suspicious nodule.
- Perifissural or subpleural nodules with typical benign morphology (triangular/lentiform, smooth) <10 mm need no follow-up, even in high-risk patients.
- Solid nodule stability over 2 years is considered benign; subsolid nodules need 5 years.
Sources
- MacMahon H, Naidich DP, Goo JM, et al. Guidelines for management of incidental pulmonary nodules detected on CT images: from the Fleischner Society 2017. Radiology. 2017;284:228–243.PubMed ↗
Radessential summarizes published classification systems for practicing radiologists. Summaries are condensed; confirm details against the cited source before relying on them for patient care.