What is a lung nodule?
A lung (pulmonary) nodule is an abnormal growth that forms in a lung. You may have one nodule on the lung or several nodules. Nodules may develop in one lung or both.
Most lung nodules are benign (not cancerous). Rarely, pulmonary nodules are a sign of lung cancer.
Lung nodules show up on imaging scans like X-rays or CT scans. Your healthcare provider may refer to the growth as a spot on the lung, coin lesion or shadow.
How common are lung nodules?
Are lung nodules a sign of lung cancer?
About 95% of lung nodules are benign. Many things can cause benign lung nodules, including infections and scarring. If you have a pulmonary nodule, your healthcare provider may want to perform additional tests to determine the cause and rule out lung cancer.
Symptoms and Causes
What causes lung nodules?
When an infection or illness inflames lung tissue, a small clump of cells (granuloma) can form. Over time, a granuloma can calcify or harden in the lung, causing a noncancerous lung nodule.
Other causes of noncancerous lung nodules include:
- Air irritants or pollutants.
- Autoimmune diseases, such as rheumatoid arthritis and sarcoidosis.
- Fungal infections like histoplasmosis.
- Respiratory system infections, such as tuberculosis (TB).
- Scar tissue.
What are the risk factors for lung nodules?
Anyone can develop pulmonary nodules. A nodule is more likely to be cancer if you:
Are a former or current smoker.
- Are older than 65.
- Have a family history of cancer.
- Received radiation therapy to the chest.
- Had exposure to asbestos, radon or secondhand smoke.
What are the symptoms of lung nodules?
Small lung nodules rarely cause symptoms. If the growth presses against the airway, you may cough, wheeze or struggle to catch your breath.
Also rarely, you could experience signs that might indicate early stage lung cancer (cancer that hasn’t spread outside the lung). Contact your healthcare provider if you have lung nodules and start to experience:
Diagnosis and Tests
How are lung nodules diagnosed?
Most people find out they have a lung nodule after getting an imaging test in preparation for a procedure or another purpose. The findings are often a surprise.
If an imaging test shows a lung nodule, your healthcare provider may recommend active surveillance. In six to 12 months, you get another CT scan. Nodules that stay the same size during a two-year surveillance period are not likely to be cancer. You may be able to stop getting CT scans.
Your provider may order further tests if the nodule is large (more than half an inch, or about 12 millimeters) or it grows. These tests include:
- Bronchoscopy: While you’re sedated, your provider threads a thin tube (bronchoscope) down your throat into the lung. A tiny surgical instrument on the end of the scope snips and retrieves a tissue sample from the nodule. A lab analyzes this biopsy sample for abnormal cells.
- CT scan-guided biopsy: For nodules on the outer part of the lung, your provider uses CT images to guide a thin needle through the skin and into the lung. This needle biopsy takes tissue samples from the nodule to examine for abnormal cells.
- Positron emission tomography (PET) scan: A PET scan uses a safe, injectable radioactive chemical and an imaging device to detect diseased cells in organs.
Management and Treatment
What are the complications of lung nodules?
Rarely, a noncancerous lung nodule may press against or block the airway. You may need surgery to clear the airway so you can breathe clearly again.
How are lung nodules managed or treated?
Small, noncancerous lung nodules don’t usually require treatment. You may need treatments, such as antibiotics or antifungal medications, if you have an infection.
If the nodule grows, causes problems or is cancerous, you may need surgery. Surgical procedures to remove noncancerous and cancerous pulmonary nodules include:
- Video-assisted thoracic surgery (VATS): During VATS, your provider inserts a thoracoscope (scope with a camera) and tiny surgical instruments through several small chest incisions. Your provider refers to images from the camera to remove the nodule.
- Thoracotomy: Your provider removes the lung nodule through a larger incision between your ribs, below your shoulder blade. For several days after the surgery, a tube drains excess fluid from your chest.
How can I prevent lung nodules?
Quitting smoking is the best thing you can do to protect your lungs. But there isn’t anything you can do to prevent lung nodules.
Outlook / Prognosis
What is the prognosis (outlook) for people who have lung nodules?
Most lung nodules aren’t cancerous and don’t require treatment. A noncancerous lung nodule shouldn’t affect your quality of life.
When should I call the doctor?
You should call your healthcare provider if you experience:
- Chest pain.
- Chronic cough or coughing up blood.
- Unexplained weight loss.
What questions should I ask my doctor?
You may want to ask your healthcare provider:
- What is the best plan of action for me?
- Do I need a biopsy?
- Should I look out for signs of complications?
A note from Cleveland Clinic
Lung nodules are fairly common and usually aren’t cause for concern. Still, it can be alarming to learn that you have a spot on your lung. Fortunately, the majority of lung nodules aren’t a sign of lung cancer. A noncancerous condition causes the abnormal growth. Most benign lung nodules don’t need treatment. If a nodule is cancerous, your healthcare provider can discuss next steps.
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