A lung biopsy is a medical procedure used to obtain a small sample of lung tissue for examination under a microscope. This tissue analysis is performed to diagnose various pulmonary conditions, such as determining if an abnormality seen on an imaging scan is due to cancer, an infection, or another form of lung disease like interstitial lung disease. The process allows physicians to identify the specific cellular makeup of a suspicious area, which is necessary for establishing an accurate diagnosis and guiding the most effective treatment plan. The method chosen for the biopsy depends on the location and size of the lung abnormality.
Preparing for the Biopsy
Preparation begins with a review of the patient’s medical history and current medications, including supplements and over-the-counter drugs. Patients are instructed to stop taking blood-thinning medications, such as aspirin or warfarin, several days before the biopsy to minimize bleeding risk. Required laboratory tests, including blood work to assess clotting factors, are performed.
Existing imaging studies, like CT scans or X-rays, are reviewed to precisely map the target area in the lung. Patients must fast after midnight on the day of the procedure to prevent complications if sedation is necessary. Finally, a responsible adult must be arranged to drive the patient home and often stay with them overnight.
The Procedural Methods
The method used to obtain a tissue sample is selected based on the location of the abnormality within the lung, with options ranging from minimally invasive needle techniques to more involved surgical approaches. Each technique offers specific advantages based on whether the suspicious area is near the chest wall or deep within the airways.
Transthoracic Needle Biopsy
A transthoracic needle biopsy (percutaneous or CT-guided) is commonly used for lesions located near the outer surface of the lung. The patient is positioned, and a CT scanner or ultrasound is used in real-time to pinpoint the exact trajectory for the needle. The skin is sterilized, and a local anesthetic is injected to numb the chest wall area.
The physician, often an interventional radiologist, makes a tiny incision and inserts a specialized hollow needle through the chest wall and between the ribs. The needle is advanced under continuous imaging guidance until the tip reaches the target tissue. A small core sample of tissue is extracted, and multiple passes may be required to gather sufficient material. After the sample is secured, the needle is withdrawn, and pressure is applied to the site to control bleeding.
Bronchoscopic Biopsy
A bronchoscopic biopsy is used for abnormalities located near the central airways or those accessible via the bronchial tubes. The procedure involves inserting a flexible tube called a bronchoscope, which has a light and camera, through the mouth or nose and down into the windpipe. Patients receive a mild sedative, and the throat is sprayed with a numbing anesthetic to suppress the cough reflex.
The physician navigates the bronchoscope through the smaller airways, using the camera to guide the instrument to the area of concern. Small tools, such as forceps, brushes, or specialized needles, are passed through a channel in the bronchoscope to collect the tissue sample. Techniques like Endobronchial Ultrasound (EBUS) or electromagnetic navigation may guide the tools to peripheral lesions. After collection, the bronchoscope is removed, and the patient is monitored as the sedation wears off.
Surgical Biopsy
Surgical biopsies, often using Video-Assisted Thoracoscopic Surgery (VATS), are reserved for cases where less invasive methods have failed or a larger tissue sample is required. This procedure is performed in an operating room under general anesthesia. The surgeon makes several small incisions in the chest wall.
A thin tube with a video camera, known as a thoracoscope, is inserted through one incision to provide a magnified view of the lung and chest cavity. Specialized surgical instruments are passed through the other small incisions to remove a section of lung tissue. VATS is less invasive than traditional open surgery because it avoids cutting through the ribs or breastbone, leading to faster recovery. A chest tube is often placed temporarily to drain air or fluid before the incisions are closed.
Immediate Recovery and Results
Following the biopsy, the patient is moved to a recovery area for observation, where nurses monitor vital signs, including heart rate, blood pressure, and oxygen saturation. A chest X-ray or CT scan is performed shortly after the procedure to check for a pneumothorax (air leaking into the space around the lung). If a small air leak is detected, the patient may be observed for a few hours; a larger leak might require a temporary chest drain and an overnight hospital stay.
For needle and bronchoscopic biopsies, most patients are discharged within a few hours once they are stable and imaging results are satisfactory. Patients should avoid strenuous activity or heavy lifting for about a week to allow the biopsy site to heal. The tissue sample is sent to a pathology laboratory, where specialists analyze the cells under a microscope. The treating physician usually contacts the patient to discuss the official results within several days to a week.