Updated December 16, 2014.

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

A lung biopsy may be recommended if you have a lung nodule or mass, or if your doctor is concerned that you may have an infection or another lung condition. What is a lung biopsy, how is it done and what are the possible complications?

What Is a Lung Biopsy?

A lung biopsy is a procedure to get a sample of suspicious lung tissue. By looking at a sample of tissue under the microscope, doctors can better determine what exactly is causing the abnormality.

Reasons for a Lung Biopsy

There are several reasons a lung biopsy may be recommended:

• To evaluate a nodule or mass seen on an imaging study of the chest, and to see if it is benign or malignant (cancerous)

• To diagnose a lung infection. This could be bacterial (such as tuberculosis), viral or fungal.
• To diagnose a lung disease such as sarcoidosis, pulmonary fibrosis, Wegener’s granulomatosis or rheumatoid lung disease
• To help determine the stage of a known lung cancer

Lung Biopsy Types and Procedures

There are four primary ways that doctors can biopsy an area of suspicious lung tissue:
Needle Lung Biopsy

In a needle lung biopsy, doctors place a long needle through your back and into your lung to get a sample of tissue. This is done with the use of a CT scanner or ultrasound to help guide the needle to the appropriate location. A needle biopsy is the least invasive way to sample a suspicious region in your lungs. But it does not always get enough tissue to adequately make a diagnosis. A needle lung biopsy is also called a "transthoracic" biopsy or a "percutaneous" biopsy.

Transbronchial Biopsy

A transbronchial biopsy is done during a bronchoscopy – a procedure in which a scope is directed down from your mouth and into the upper airways of your lungs.

With the help of an ultrasound (endobronchial ultrasound), physicians can then direct a needle into a suspicious area and obtain a sample (transbronchial needle aspiration.) This procedure is most effective when an abnormality or tumor is located in or near the large airways of the lungs.

Thoracoscopic Lung Biopsy

In a thoracoscopic lung biopsy, a scope is introduced through the chest wall and into the region of the lung to be biopsied. During a thoracoscopic biopsy a video camera is used to help doctors find and biopsy the area of tissue. In this procedure, also known as video-assisted thoracscopic surgery (VATS), doctors may also be able to remove an area of suspicious tissue or a lobe of the lung that is cancerous. (Note: They will not do this without discussing this with you before the procedure.)

Open Lung Biopsy

As the most invasive way to sample tissue, an open lung biopsy is sometimes necessary to sample tissue when other methods have failed. This is a major surgical procedure, done under general anesthesia. It may require separating the ribs or removing a portion of a rib to gain access to the lungs. Sometimes, an open biopsy is performed as part of surgery to remove a nodule or mass.

Results

If your doctor is able to get a good sample of tissue, you will likely hear about the results within two to three days - although this sometimes takes longer, especially if more than one pathologist wishes to review the results. It is helpful to ask your doctor at the time of the procedure when you can expect to hear your results. Some physicians are comfortable calling you on the phone to let you know their findings, while others may wish to set up a follow-up appointment to go over the results.
Though your doctor may have a good idea of what the findings will be, it’s not uncommon for physicians to be wrong after seeing a sample of tissue. The likelihood of an abnormality being cancerous depends on many factors, one of which is size. Lung nodules (spots on the lung that are 3 centimeters [1½ inches] or less) are less likely to be malignant than lung masses (spots on the lung that are greater than 3 centimeters in size). A list of some of the possible causes can be seen by clicking on the links below.

• Causes of Lung Nodules
• What Are the Causes of a Lung Mass?
• Differences Between Benign and Malignant Tumors

On occasion, a sample of tissue does not reveal a diagnosis. A report such as this may be returned as "inconclusive." If that is the case, there are still several options. If the likelihood is low that the abnormality in your chest is cancer, you may opt to wait and do a repeat scan in a few months. Similarly, even if the spot may be cancerous and having a precise diagnosis wouldn’t alter treatment, you may choose to wait.

If on the other hand a diagnosis is important, you and your doctor may choose to repeat the biopsy or find a different means of obtaining a tissue sample.

Risks

The risks of a lung biopsy vary depending on the type of procedure, the location of the tissue and your general health. The most common complications are bleeding or an air leak from your lung. Other possible complications include:

• Pneumothorax - a collapse of the lung (air leak)
• Bleeding
• Infection
• Risk of anesthesia. Both local anesthesia and general anesthesia can carry risks.
• Systemic air embolism – a leak of air into the major arteries that can travel to the heart; occurs in less than 1% of needle lung biopsies
• Tumor "seeding" – risk that a tumor will spread along the track of the needle (rare)

Your Emotions Before a Lung Biopsy

Whatever the reason your doctor has recommended a lung biopsy, the uncertainty can be hard to cope with. Many people have said that they feel more at peace with a bad diagnosis than living in a state of not knowing.
Lean on your family and friends and this time. Reach out to people you know will help you cope with the waiting, such as those who usually raise your spirits. This is also a good time to kindly ask your loved ones not to "diagnose" you until you know more, and to refrain from sharing their stories (what I call horror stories) about others who have faced something similar.

If your mind goes to the worst-case scenarios, keep in mind that medicine is always changing. If you do have the same diagnose your grandmother did years ago, it does not mean you will have the same experience.

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National Institute of Health. MedlinePlus. Lung needle biopsy. Updated 08/30/12. http://www.nlm.nih.gov/medlineplus/ency/article/003860.htm

National Institute of Health. MedlinePlus. Open Lung Biopsy. Updated 12/10/12. http://www.nlm.nih.gov/medlineplus/ency/article/003861.htm

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