What are Lung Nodules?

A lung nodule is a small round mass of tissue on the lung, also called a pulmonary nodule, a spot on the lung, or a coin lesion. Lung nodules range in size but are usually no larger than about 0.4 inches (one centimeter). Growths in the lung tissue larger than 1.2 inches (3 cm) are called lung masses. Lung nodules can be benign or malignant.

Signs of Lung Nodules

Lung nodules typically do not come with noticeable symptoms. Most people do not know they have a lung nodule until a doctor sees it on an x-ray or CT scan. If someone with lung nodules does have symptoms, they are usually related to the condition causing the growths. For instance, an individual may visit the doctor complaining of respiratory illness or flu-like symptoms and later learn he or she has lung nodules.

Diagnosing a Spot on the Lung

A doctor will typically diagnose a lung nodule with an x-ray or CT scan. The spots will appear as white shadows on the imaging results. Lung nodules show up on at least one out of every 500 x-rays, according to statistics. Lung nodules are often harmless but can also indicate serious medical conditions.

Evaluating Test Results

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.

Size Matters

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.

Examining Lung Nodules

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.

Diagnosing Lung Nodules: Needle 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.

Diagnosing Lung Nodules: Bronchoscopy

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.

Diagnosing Lung Nodules: Thorascopic Biopsy

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.

Removing Lung Nodules: Thoracotomy

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.

Removing Lung Nodules: Video-Assisted Thorascopic Surgery

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.