| Solid Nodule | <6mm | 6-8mm | >8mm | Notes |
| Single | ||||
| Low risk | No routine f/u | CT @ 6-12 months, then consider CT @ 18-24 months | Consider CT, PET/CT or biopsy @ 3 months | <6mm do not require f/u, but high risk patient or nodule characteristics may warrant 12 month f/u. |
| High risk | Optional 12 month CT | CT @ 6-12 months, then consider CT @ 18-24 months | Consider CT, PET/CT or biopsy @ 3 months | |
| Multiple | ||||
| Low risk | No routine f/u | CT @ 3-6 months, then consider CT @ 18-24 months | Use most suspicious nodule to guide management | |
| High risk | Optional 12 month CT | CT @ 3-6 months, then @ 18-24 months | ||
| Sub-solid nodule | <6mm | ≥6 mm | Notes |
| Single | |||
| Ground glass | No routine f/u | CT @ 6-12 mo to confirm persistence, then q 2 years until 5 years | For suspicious nodules <6mm, consider 2 and 4 year f/u. |
| Part solid | No routine f/u | CT @ 3-6 months to confirm persistence. If stable and <6mm solid component, then q12 months for 5 years | <6mm part solid nodules too small to be defined. Persistent part-solid nodules with >6mm solid component are highly suspicious. |
| Multiple | CT @ 3-6 months. If stable, consider CT @ 2 and 4 years | CT @ 3-6 months. Subsequent management based on most suspicious nodule(s) | Multiple <6mm ground-glass nodules usually benign. May consider f/u @ 2 and 4 years in high-risk patients. |
References:
MacMahon, H., et al. (2017). “Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images: From the Fleischner Society 2017.” Radiology: 161659.