A shadow on your scan isn’t always serious, but it deserves attention.
A pulmonary nodule—sometimes called a “spot on the lung”—is a small mass of tissue that appears on imaging scans. These growths are usually less than a centimeter in diameter and often go unnoticed until picked up on an x-ray or CT scan. While most nodules are benign, some require further testing to rule out cancer or other serious conditions. Understanding how they’re found, diagnosed, and treated is key to early intervention and peace of mind.
Most lung nodules don’t cause symptoms and are often discovered by accident during imaging for unrelated health concerns. In rare cases, people might visit the doctor with symptoms like a persistent cough, fatigue, or signs of respiratory infection—only to later learn they have one or more nodules. When symptoms do occur, they’re typically caused by the underlying condition rather than the nodule itself.

Pulmonary nodules are typically identified through chest x-rays or CT scans. On these images, nodules show up as small white shadows. While they’re relatively common—especially in older adults or people with prior lung infections—the discovery always warrants follow-up to rule out cancer, infections, or autoimmune disease.

If the doctor notices a lung nodule on an x-ray or CT scan, he or she will inquire as to past and current risk factors for cancer, such as smoking, family history, and exposure to toxic chemicals. Fungal and bacterial infections cause inflammation that can create pulmonary nodules. Conditions such as sarcoidosis can also cause masses to form on the lung through the accumulation of inflammatory cells. Lung cancer, lymphoma, and cancers that have metastasized from other parts of the body can also cause malignant tumors.

The doctor also considers the size of the lung nodule when making diagnosis and treatment recommendations. If a nodule is small and there are no other risk factors, the doctor may suggest waiting to see if the size or shape of the mass change over time. If nodules are large or are known to have grown, the doctor will likely suggest treating them. A doctor is more likely to recommend further testing if the patient has a history of smoking or a significant family history of lung cancer.

The doctor may run various tests to see if the lung nodules are cancerous. A closed lung biopsy can be done laparoscopically through the skin or trachea. An open biopsy requires general anesthesia. Procedures include needle biopsy, bronchoscopy, and video-assisted thoracic surgery biopsy.

During a needle biopsy, a thin hollow needle is inserted into the nodule while the surgeon watches the lungs via a CT scan. A sample of tissue is extracted and inspected under a microscope. This procedure is also called a closed, transthoracic, or percutaneous biopsy. Closed biopsies are less invasive than open biopsies, and require less recovery time; they are often out-patient procedures.

Needle biopsies may not be possible for smaller lung nodules or masses in certain parts of the lung. A bronchoscopy is a more suitable method for testing nodules that are accessible through the breathing tubes. During this procedure, a doctor inserts a flexible tube into the mouth or nose and feeds it through the windpipe and into the airway.

A thorascopic biopsy involves making an incision in the chest and surgically removing a small piece of the lung. In this way, the doctor can examine the outer lungs and inner rib cage, noting any abnormal areas.

Surgeons employ two methods to surgically remove lung nodules. The first of these is a thoracotomy. This open procedure requires an incision in the wall of the chest that allows the surgeon to remove pieces of affected lung tissue. The procedure usually requires a few days' stay in the hospital. A mini-thoracotomy is a less invasive alternative to a full thoracotomy.

For this procedure, the surgeon creates an incision in the wall of the chest and inserts a small camera and tools. The process allows the doctor to view the nodules and remove any lesions or tumors. People typically recover more quickly from this surgery compared to thoracotomy surgery because it is less invasive.

This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.