Guidelines from the Fleischner Society


Low-risk patients (Minimal or absent history of smoking and of other known risk factors.):


Less than or equal to 4 mm - No further investigation

4-6 mm - CT scanning at 12 months

6-8 mm - CT scanning at 6-12 months and 18-24 months

Greater than 8 mm - CT scanning at 3, 9, and 24 months; contrast-enhanced CT scanning; positron-emission tomography (PET) scanning; and/or biopsy




High-risk patients (History of smoking or of other known risk factors.)


Less than or equal to 4 mm - CT scanning at 12 months

4-6 mm - CT scanning at 6-12 months and 18-24 months

6-8 mm - CT scanning at 3–6 months, 9–12 months, and 24 months

Greater than 8 mm - Same as low-risk patients





The American College of Chest Physicians (ACCP) proposed new guidelines in 2007 for the management of solitary pulmonary nodules:


- Carefully calculate pretest probability for malignancy, either through experienced clinical judgment or through the use of a validated model.


- Previous chest radiographs should be reviewed to determine if the lesion has been stable over 2 years. If so, no further follow up is necessary, with the exception of pure ground-glass lesions on CT scans, which can be slower growing.


- For lesions with a benign pattern of calcification, further testing is not necessary.


- Management of indeterminate lesions greater than 8-10 mm depends on clinical probability of malignancy, as follows:

- Low probability: Serial CT scanning at 3, 6, 12, and 24 months

- Intermediate probability: 18-Fluorodeoxyglucose (FDG) PET scanning, contrast-enhanced CT scanning, transthoracic needle aspiration (TTNA), and/or transbronchial needle aspiration (TBNA)

- High probability: Surgical resection


- Subcentimeter lesions - Same as Fleischner Society, as listed above


- Any unequivocal growth noted during follow up = Definitive tissue diagnosis needed




Source : Guidelines for management of small pulmonary nodules detected on CT scans: a statement from the Fleischner Society - Radiology. 2005 Nov;237(2):395-400.

See results

Dr Antoine Micheau
CHU Arnaud de Villeneuve
Radiological classifications commonly used in medical imaging
Solitary Pulmonary Nodule Solitary-Pulmonary-Nodule-Guidelines-from-the-Fleischner-Society