A percutaneous lung biopsy is a medical procedure that obtains small tissue samples from the lung for examination. This minimally invasive technique involves inserting a needle through the skin and chest wall, guided by imaging like a computed tomography (CT) scan, to reach the area of concern. The procedure helps analyze lung abnormalities and determine their nature.
Why a Lung Biopsy is Needed
A percutaneous lung biopsy investigates suspicious areas found on imaging tests like chest X-rays or CT scans. These abnormalities, such as nodules or masses, are biopsied to determine if they are benign (non-cancerous) or malignant (cancerous). The procedure has a diagnostic yield estimated at 93% for lung cancer.
Beyond cancer, a biopsy can diagnose various lung conditions. It identifies infections, like those caused by fungi or bacteria, when other methods are inconclusive. Biopsies also help pinpoint the cause of inflammatory lung conditions or obtain tissue for molecular testing, which guides targeted therapies for lung cancer. This method is useful for patients not suitable for more invasive surgical procedures.
Preparing for and Undergoing the Biopsy
Before a percutaneous lung biopsy, patients undergo a medical assessment, including a review of their health history, a physical examination, and routine blood tests. These tests include evaluating blood clotting abilities. Patients must stop taking blood-thinning medications, such as aspirin, several days before the procedure, typically 5 to 10 days, to minimize bleeding risk. Fasting is also required, with specific instructions provided by the medical team, often involving no food or drink after midnight on the day of the procedure.
On the day of the biopsy, patients arrive, complete consent forms, and may have an intravenous (IV) line placed. A local anesthetic is injected into the chest wall to numb the area, which might cause a brief stinging sensation. Sedation may also be administered to help patients relax and remain still during the procedure, which generally takes 30 to 60 minutes.
During the biopsy, a radiologist uses CT guidance to precisely locate the abnormal lung tissue. A biopsy needle is then inserted through the numbed skin into the targeted area. The radiologist carefully plans the needle’s path to avoid major blood vessels and airways. Multiple tissue samples are often collected using a coaxial technique, where a larger introducer needle is placed, and smaller biopsy needles are passed through it to obtain several samples with a single puncture of the pleura, the lining around the lung.
Understanding Potential Risks
A percutaneous lung biopsy carries potential complications. The most common risk is pneumothorax, or a collapsed lung, which occurs when air leaks into the space between the lung and the chest wall. This complication is reported in approximately 17% to 26.6% of cases, with about 1% to 14.2% requiring a chest tube for drainage. Factors like underlying lung disease, lesion size, and depth can influence the risk of pneumothorax.
Bleeding is another common complication, often presenting as small amounts of blood in the sputum, which usually resolves on its own. Pulmonary hemorrhage, or bleeding within the lung, is observed in 4% to 27% of patients. Less common but more serious risks include air embolism, where air enters the bloodstream and can travel to the heart or brain, and infection, though these are rare. The risk of severe bleeding requiring intervention or an air embolism is low, around 1 in 1,000 to 1 in 3,000 procedures.
What to Expect After the Procedure
Following a percutaneous lung biopsy, patients are monitored for a few hours in a recovery area. This includes checking vital signs. A chest X-ray is often performed immediately and again a few hours later to check for signs of a pneumothorax or bleeding. Most individuals can return home several hours after the procedure; some may require an overnight hospital stay if complications arise.
Pain around the biopsy site is common and usually improves within a few days. Patients may also experience minor blood streaks in their mucus for up to a week. Activity restrictions are advised for about a week, including avoiding heavy lifting and strenuous exercise. Patients are also advised to avoid flying or deep diving for a period after the procedure due to changes in air pressure.
Tissue samples are sent to a laboratory for examination, with results typically available within 7 to 10 working days. A follow-up appointment with the referring healthcare provider is then scheduled to discuss the findings and determine the next steps in treatment or management.