2017 guidelines — follow-up for an incidental pulmonary nodule on CT
Nodule type
Solid
Ground-glass (pure)
Part-solid
Nodule size (average of long and short axis) mm
Multiple nodules present
Select the nodule type and enter its size to calculate
Evidence
Original publication
MacMahon H, Naidich DP, Goo JM, et al. Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017. Updated the follow-up intervals and size thresholds for solid and subsolid nodules used here, replacing the separate 2005 (solid) and 2013 (subsolid) Fleischner guidelines.
Radiology, 2017
Open source
Guideline
These recommendations are for an incidental nodule in an adult and do not apply to lung cancer screening (Lung-RADS applies there instead), a patient who is immunosuppressed, or a patient with a known primary cancer (where the nodule may be a metastasis and closer follow-up is usually appropriate). A nodule ≥ 3 cm is conventionally a mass and is managed as a suspected malignancy rather than followed per this guideline. For multiple nodules, use the most suspicious nodule to guide management; follow-up intervals may vary with its size and risk.
Last reviewed: 2026-09
Report an error in this calculator
MedScore is an educational and clinical decision-support tool. It does not provide a diagnosis, a treatment, or a drug-dosing recommendation, and it does not replace clinical judgement or local guidelines. Confirm every result against the original source before acting on it. The treating clinician remains responsible for all decisions.