Lung nodules are small growths in your lungs less than 30 mm in diameter. Many nodules aren’t cancerous, but the risk becomes higher with increased size.
A lung nodule is a small irregular growth in your lungs that’s smaller than 30 millimeters (mm) (1.2 inches) in diameter. They’re very common and estimated to occur in anywhere from
Most lung nodules aren’t cancerous. Noncancerous causes include:
- infections
- rheumatoid arthritis
- benign lesions (such as hamartomas)
Nodule size and growth rate are the two main factors doctors use to determine the risk of a nodule being cancerous, along with shape and pattern of calcification.
Small nodules often don’t require treatment. Doctors may recommend follow-ups or surgery for large nodules, especially if you’re somebody at a high risk of developing lung cancer.
Read on to learn more about how lung nodule management varies by size.
Most nodules don’t cause symptoms and don’t require treatment. Larger nodules are more likely to be cancerous and require surgical removal.
The
Their guidelines advise doctors on how to manage lung nodules based on factors such as:
- nodule size
- how quickly the nodule grows
- tissue composition of the nodule
Their guidelines don’t apply to people younger than 35 or with a history of cancer or immunosuppression.
What’s considered a small lung nodule?
Lung nodules are usually considered small if they’re under
Here’s a look at the risk of small nodules becoming cancerous.
| Diameter size | Risk of being cancerous |
|---|---|
| 1–2 mm | These nodules are routinely found and have a very small risk of being cancerous. |
| Under 6 mm | Studies report anywhere from a 0%–1% chance of being cancerous. |
| 6–8 mm | These nodules have about a |
| More than 8 mm | There’s about a |
| More than 10 mm | These have about a |
What’s considered a large lung nodule?
Large nodules are usually considered to be greater than 10 mm in diameter. The risk of them being cancerous increases as they become bigger. By definition, a nodule is smaller than 30 mm.
| Diameter size | Risk of being cancerous |
|---|---|
| Larger than 10 mm | The chances of nodules larger than 10 mm being cancerous are about |
| Larger than 30 mm | Tumors larger than 30 mm are considered lung masses and are |
If you’re at low risk of developing lung cancer, a doctor will likely tell you that you don’t need regular follow-ups for nodules under 6 mm. Younger age and not smoking are associated with low risk. A doctor may want to follow up with a CT scan if you’re at high risk.
A doctor will likely want to monitor nodules that are between
For nodules larger than 8 mm, a doctor will likely want to follow up with some combination of:
- repeated CT scans
- positron emission tomography (PET)/CT scan
- tissue biopsy
The next step depends on:
- how large the nodule is
- how many nodules a doctor finds
- tissue features of the nodule
Depending on how the cells look with a CT scan, doctors classify nodules as:
- solid
- subsolid
- ground-glass
- part-solid
Here’s a look at the Fleischner Society guidelines for each type.
Recommendations for single solid nodule
| Size | Treatment |
|---|---|
| Smaller than 6 mm | low risk: no routine follow-up needed high risk: optional CT scan at 12 months |
| 6–8 mm | low risk: CT scan at 6–12 months and possibly at 18–24 months high risk: CT scan at 6–12 months and again at 18–24 months |
| Greater than 8 mm | CT scan at 3 months and possibly PET-CT scan or biopsy |
Recommendations for multiple solid nodules
| Size | Treatment |
|---|---|
| Smaller than 6 mm | low risk: no routine follow-up needed high risk: optional CT scan at 12 months |
| Greater than 6 mm | low risk: CT scan at 3–6 months and possibly at 18–24 months high risk: CT scan at 3–6 months and again at 18–24 months |
Recommendations for single subsolid nodules
| Size | Treatment |
|---|---|
| Ground-glass nodule smaller than 6 mm | no follow-up required |
| Ground-glass nodule greater than 6 mm | CT scan at 6–12 months and every 2 years for 5 years if they persist |
| Part-solid nodule greater than 6 mm | CT scan at 3–6 months CT scan every year for 5 years if solid component remains under 6 mm |
Recommendations for multiple subsolid nodules
| Size | Treatment |
|---|---|
| Smaller than 6 mm | CT scan at 3–6 months if stable, CT scan at 2–4 years in high-risk people |
| Greater than 6 mm | CT scan at 3–6 months management based on the most suspicious nodule |
A doctor may recommend a biopsy if repeat CT scans show that the nodule is getting bigger over time or has concerning features.
A biopsy can be performed in
- with a long tube that goes down your throat called a bronchoscope
- with a hollow needle through your chest wall with CT guidance
- with surgery to remove the nodule and surrounding lung tissue
- smoking
- increased age
- prior lung infection
- prior history of cancer
- interstitial lung disease
- emphysema
- exposure to chemicals like asbestos, radon, or uranium
You may be able to minimize your chances of developing lung nodules by quitting smoking if you currently smoke or by avoiding smoking if you don’t. This can be difficult, but a doctor can build a cessation plan that works for you.
Minimizing your exposure to cancer-causing substances like uranium and wearing proper safety equipment when you do handle them may also lower your risk.
Lung nodules are small growths in your lungs less than 30 mm in diameter. The majority of these nodules aren’t cancerous, but the risk becomes higher with increased size.
A doctor may want to perform regular follow-ups for nodules larger than 6 mm or for smaller nodules if you have a high risk of lung cancer.
A doctor may recommend a biopsy or surgical removal of nodules that are growing or have concerning features.