Overview of Percutaneous Lung Lesion Biopsy
A percutaneous lung lesion biopsy (PLLB) is a test where a needle is carefully passed into the lung to take a small tissue sample. This is done using a special type of X-ray machine called a thoracic computed tomography scan to help guide the needle to the right spot. This type of biopsy is usually done to diagnose lung cancer and is considered an accurate way to do so, with a success rate of about 93%.
However, it’s important to note that this procedure is considered to have high risk of complications, with about 35% of patients experiencing issues afterward. The ease or difficulty of the procedure can vary greatly from patient to patient. For some, it can be completed in less than 30 minutes without any issues. For others, it may require multiple attempts, taking over 90 minutes and still not yield a successful tissue sample. This article will discuss with you the important aspects of a PLLB, including what to expect before, during and after the procedure, and potential complications that can occur.
Anatomy and Physiology of Percutaneous Lung Lesion Biopsy
The lungs have five parts or sections which are known as lobes. The right side of the lungs has three lobes, and the left side has two lobes. Around these lobes, there are thin layers of tissue named pleural membranes. The one lining the inside of your chest wall is called the parietal pleura, and the one wrapping around the lungs is known as the visceral pleura. In between these two layers, there is a small space filled with a tiny amount of fluid which helps the layers slide against each other easily. This sliding motion is important to allow the lungs to expand and deflate smoothly when you breathe.
Blood is supplied to the lungs through two types of arteries: bronchial and pulmonary arteries. Bronchial arteries, usually two to the left lung and one to the right lung, come from the aorta, the main blood vessel from the heart. They split up to follow the pathways of the bronchi and bronchioles, the tubes that carry air into your lungs. The pulmonary arteries get their blood from the right side of the heart and there is typically one for each lung. These arteries also split up to supply each lobe of the lung with blood.
When doctors suspect that something might be wrong with the lungs, a special type of X-ray called computed tomography (CT scan) is critical in deciding the best approach to examine the abnormality. Depending on the location and size of the abnormal area, they could choose a bronchoscopic biopsy (using a bronchoscope), a surgical biopsy (often using a procedure involving a camera called video-assisted thoracoscopic surgery), or a percutaneous needle biopsy (using a needle to take a sample). Surgical biopsies are usually chosen for suspected cases of interstitial lung disease (a group of diseases that cause scarring of lung tissue) or small peripheral lesions. Bronchoscopic biopsy is often the choice for lesions located centrally in the lung.
Why do People Need Percutaneous Lung Lesion Biopsy
When doctors need to examine a suspicious spot or mass in the lungs, they often use a procedure called Percutaneous Lung Lesion Biopsy, or PLLB. This procedure is particularly useful when it’s unclear if the mass is something that should be treated with chemotherapy or radiation, rather than surgery. It’s very useful for patients who have had cancer elsewhere in their body. Doctors also use it to take small samples of tissue to test in a lab. This technique is becoming increasingly important to treat lung cancer, as doctors can identify specific changes in genes and can give medicines that specifically target these changes.
This procedure isn’t just for lung cancer. PLLB is also used to detect important factors in breast cancer that’s spread to the lungs, as well as to diagnose certain lung infections. It’s also used to get to hard-to-reach spots in the chest wall and the area around the lungs and heart, known as the mediastinum and pleura.
According to guidelines from the National Comprehensive Cancer Network, the American College of Chest Physicians, and the American Society of Clinical Oncology, doctors don’t always need to do a biopsy before surgery if it is strongly suspected that the patient has early-stage lung cancer. However, a biopsy might be necessary if it’s believed the mass could be something other than lung cancer, or if it would be particularly risky or difficult to identify during surgery.
Doctors recommend certain tests before surgical removal of a lung tumor, depending on the tumor’s size and location, whether the disease has spread, the patient’s overall health, and the doctor’s expertise. For the majority of patients with nonsmall cell lung cancer, which is a common type of lung cancer, removal of a portion of the lung is usually the best option. If doctors suspect that the cancer has spread, they should try to confirm this from a sample taken from one of the places where the cancer has spread. However, if taking a sample from one of these places is too risky or difficult, a biopsy of the main lung tumor or lymph nodes in the mediastinum should be performed.
If a patient is suspected to have several distant sites of spread, and taking a biopsy from these sites would be too risky, then it’s recommended to diagnose the main lung lesion using the least invasive method. If the patient has a nodule on the lung that needs to be diagnosed because it’s unclear what it is or the patient is not a good candidate for surgery, a radial endobronchial ultrasound (EBUS) is recommended. If EBUS can’t be done, then an electromagnetic navigation guidance procedure might be done. If these options aren’t available, then doctors would likely use PLLB.
Finally, if a doctor suspects a small lesion on your lung to be cancer and you’re a candidate for surgery, a biopsy might not be done before going straight to surgical removal. When the spotting on the lung seems to likely be cancer, surgery is the best option for both diagnosing and treating the condition. If it’s unclear whether the spot is cancer, then a biopsy is advisable.
The latest update from the National Comprehensive Cancer Network in 2022 recommends testing for certain changes in genes from tissue samples taken from lung biopsies. This is especially important for patients with advanced or spread nonsmall cell lung cancer, as identifying these changes can help target treatment more effectively.
When a Person Should Avoid Percutaneous Lung Lesion Biopsy
There are some circumstances where a type of lung biopsy known as PLLB might not be possible due to various issues. These include situations where:
- The patient can’t cooperate due to various reasons
- The patient has high blood pressure in the lungs (diagnosed usually by computing scanning or directly by examining the right side of the heart)
- The patient needs help to breathe using positive-pressure ventilation
- The patient has severe respiratory failure which requires using additional oxygen
- The patient has severe bullous emphysema, a lung condition causing breathlessness
- The patient has extensive disease affecting the lining of the lungs
- The patient has a history of removal of lung(s) on opposite side
- The patient has severe lung fibrosis that’s close to the terminal stage
- The patient’s lungs have a severe impairment in absorption of carbon monoxide
- The patient has a chronic cough that can’t be controlled
- The patient has severe interstitial lung disease, an illness affecting the space and tissue within the lungs
- The patient’s blood fails to clot properly
- The patient has small lesions (less than 1 cm) located near the diaphragm or central lesions close to a large blood vessel
- The person has abnormal blood clotting results (platelet count less than 100,000/mL or clotting time ratios greater than 1.4).
Before doing the biopsy, doctors will typically check platelet count, clotting time and related measures. If the patient is taking certain blood thinners, these may need to be paused several days before the procedure. If clotting time exceeds a safe limit, it may need to be corrected using methods like certain kinds of transfusions or vitamin K. These are to make sure that doctors can manage bleeding well during the process.
According to standards, blood thinners and anticoagulant medicines are stopped based on how much risk of bleeding each procedure has. The PLLB procedure is placed under level 2 category according to a risk classification system developed by Johns Hopkins. This is classified considering the need for blood replacement. The risk is comparable to laparoscopic removal of gall bladder or repair of the groin hernia. Potential complications that may occur during this biopsy include chest pain similar to that experienced during a heart attack.
One of the important things for the PLLB procedure is the cooperation of the patient. As this procedure is often done on moving parts without real-time imaging to guide, patient’s stability in terms of breathing and lying still is important. If a patient is unable to cooperate, it could be a major barrier to the procedure. In many cases, measures can be taken to improve a patient’s ability to stay still and cooperate.
To make the patient comfortable and immobile during the procedure, conscious sedation (a state where the patient is awake but relaxed and pain-free) is often used. It may be especially helpful for those who are anxious, older adults who experience arthritic discomfort, or when biopsies of small lesions close to diaphragm or large central blood vessels are involved. However, in cases of patients with severe heart or lung problems, this sedation process might not be suitable.
Equipment used for Percutaneous Lung Lesion Biopsy
When performing a Percutaneous Lung Lesion Biopsies (PLLB), which is a procedure to collect a sample of lung tissue, imaging plays a crucial role. One tool used for this is a Computed Tomography (CT) scan, a special type of X-ray machine that produces detailed images of internal structures. This imaging technique is often preferred due to its ability to visualize the lung tissue and any abnormalities present. The use of a CT scan allows doctors to place the biopsy needle accurately and safely, to maximize the chance of getting a good tissue sample while minimizing the risk to the patient.
Although CT scans are the primary imaging method, ultrasound or a technique known as fluoroscopy might also be used, depending on the particular characteristics of the lung tissue that needs to be sampled and the expertise of the medical team. Ultrasound, which uses sound waves to create images, is especially useful for peripheral lesions, which are abnormalities located near the outer edges of the lungs. It allows doctors to see what they’re doing in real time, without exposing the patient to radiation. Fluoroscopy, which uses continuous X-ray to create real-time images, also provides real-time visualization and can be used for more complex cases.
Despite the preference for CT scans, we should take into account the potential risk of radiation exposure to the patient during these procedures. Therefore, a technique called CT fluoroscopy, which combines the benefits of a CT scan and fluoroscopy, is becoming more popular. It provides real-time imaging, useful for challenging cases. However, this method can expose the healthcare provider to radiation. For peripheral lesions, ultrasound guidance can be a safer choice, since ultrasound does not involve radiation exposure and still provides effective guidance for the placement of the biopsy needle.
In terms of treatment, an unenhanced CT scan is usually enough to locate the lesion since lung tissue and nodules appear different on the scan. However, in some cases, a solution known as an intravenous contrast agent may be used to better define certain structures that lie in the anticipated path of the biopsy needle.
Before performing the PLLB, doctors ensure patients and the room setup is appropriate to handle possible emergencies. The following equipment should be readily available in case of any complications:
For all patients:
- A vital signs monitor for tracking heart rhythm, blood pressure, oxygen levels, and carbon dioxide levels
- A working Intravenous (IV) line for giving medications or fluids as needed
For the room setup:
- Oxygen supply to make sure the patient gets enough oxygen
- Special suction devices for keeping the patient’s airway clear if needed
- Equipment to help the patient breathe if they have trouble doing it on their own
- A resuscitation cart with essential emergency medications and equipment
In cases where there’s a risk of pneumothorax, a condition when air leaks into the space between the lung and chest wall, the following equipment should be nearby:
- Specific needles for inserting a chest tube, a thin, hollow tube that’s inserted between the ribs to help drain air and allow the lung to re-expand
- Chest tubes of different sizes, chosen based on the specific situation
- A special one-way valve or stopcock to help with chest tube insertion and drainage
- A resuscitation device for emergency treatment of cases when air pressure in the chest becomes dangerously high
- A wall suction device to help drain the chest
- A chest drainage system to manage long-term cases of pneumothorax, hydrothorax (accumulation of fluid in the chest), or hemothorax (accumulation of blood in the chest)
- Connecting stopcocks and tubes for proper drainage and monitoring
Having all of this equipment ready helps ensure that any complications that occur during the PLLB can be managed promptly and effectively.
Preparing for Percutaneous Lung Lesion Biopsy
Before a procedure called a Percutaneous Lung Lesion Biopsy (PLLB), doctors perform a thorough patient assessment. This includes understanding the patient’s medical history, doing a physical examination, and conducting routine lab tests. Especially for patients with a higher risk of bleeding, doctors need to do tests to evaluate blood clotting abilities. These tests measure things like prothrombin time (PT), activated partial thromboplastin time (aPTT), and the number of platelets in the blood – all of which have to do with your blood’s ability to form clots.
It’s crucial to strictly follow guidelines on blood thinning medications, often having to stop taking these medications before the procedure to minimize the risk of bleeding complications. Monitoring lung function before an operation is imperative, and patients who have less than 35% of their expected ability to exhale in one second may need extra evaluation before being sanctioned for a biopsy.
The medical team will also review your previous chest x-rays and CT scans before the procedure. It is crucial to follow the guidelines provided by the profession, especially those by The Society of Interventional Radiology, to ensure the patient’s safety and well-being.`
It’s important that patients understand the procedure. Everyone has their own ability to understand instructions and maintain positions required during the biopsy. This can be more challenging for those with conditions like shortness of breath, arthritis, hearing impairments or those suffering from lack of sleep. Therefore, proper communication and preparation on the patient’s part, like practicing consistent breath holds, go a long way in ensuring the procedure is problem-free.
During the procedure, the prone position (lying flat and face down) is often preferred. This position has several benefits such as less movement of the ribs, wider spaces between the ribs, not being able to see the needle during the procedure, and being able to recover comfortably lying face-up. Other positions like the lateral (lying on the side) or supine (lying face-up) positions cause more movement, thereby increasing the risk of complications.
Peripheral thoracic locations – the areas towards the sides of the chest – are also usually chosen over the central lungs for the biopsy as these areas have lesser vessels, reducing the risk of complications during the biopsy. Similarly, avoid going in through the already aerated lung tissue, as it decreases the risk of pneumothorax – a potential complication where air leaks into the space between your lung and chest wall, causing the lung to collapse.
Large lesions- abnormal areas of tissue, are easier to hit and are preferred over smaller ones. But more than size, the location of the lesion is important as well. Lesions that are closer to the outer lining of the lung and those that are visibly distinct or show a specific pattern of metabolic activity (how the cells in the lesion consume energy) can be easier and safer to access.
Other factors that can influence the choice of lesion are whether you’ve had any chest surgeries before, as these can cause scarring and increase the risk of pneumothorax. Avoid puncturing directly through the scar, as the presence of harder tissue can make it more difficult to manipulate the needle.
In conclusion, every detail matters when it comes to a lung biopsy, from pre-procedure assessments to the patient’s behavior during the procedure, to selecting the appropriate lesion and positioning the patient. All these factors are carefully considered to ensure the procedure is successful while minimizing any possible complications.
How is Percutaneous Lung Lesion Biopsy performed
When a doctor extracts a sample from a lesion (an abnormal tissue) in your body, a method called the coaxial technique can be used. This technique involves inserting a small sampling needle through a larger needle already positioned at the edge of the problem area. The coaxial method can have various advantages over a technique involving multiple separate punctures into your skin.
Firstly, the coaxial technique allows multiple samples to be taken without creating multiple points of entry into the tissue, which can cause additional pain. This method is also faster and leads to a reduced risk of complications from multiple punctures.
Additionally, this technique allows for better depth control and maneuverability since a stiffer, larger needle is used. This aids in accurately targeting the lesion and increases the chance of obtaining enough samples.
If there are complications during the procedure, like the trapping of air between the lung and chest wall (also called pneumothorax), the introducer needle (the larger needle) often remains stuck in the lesion. This allows for the potential to take more samples and assists in managing the pneumothorax.
Furthermore, the larger needle chosen for the coaxial technique can serve more than one purpose. It can be used to obtain a tissue sample, insert a marker in the diseased area for further procedures like surgical removal or radiation therapy, or deliver a substance to seal the path created during the procedure.
By reducing the number of puncture sites, there is less risk of developing pneumothorax. When you cough, the pressure can be high enough to allow air to enter through non-patched or patched puncture areas. Keeping these to a minimum is, therefore, extremely important.
However, in some cases, especially when there is a high risk of bleeding, the adoption of a single puncture technique can be more suitable. This method requires a more targeted approach to the lesion and minimizes complications due to multiple punctures. It also allows more precise procedures, reducing risks, especially when the lesions are close to critical areas or there’s a high chance of bleeding.
A careful evaluation of every case is vital, considering factors like the specific characteristics of the lesion, the patient’s overall health conditions, and the expertise of the healthcare team. The choice of technique should be personalized based on the potential benefits and risks of the procedure.
During the procedure, it’s important to breathe normally. If the lung is punctured during deep inhalation or exhalation, it can put tension on the needle when the lung returns to its normal state, increasing the likelihood of tearing the tissue around the puncture site.
Certain precautions need to be taken to reduce the risk of complications during the procedure. These include managing time effectively to keep the procedure short and reducing unnecessary delays, interrupting procedures during coughing episodes, and closing the puncture site to prevent gas leakage. If the presence of pneumothorax is known, giving the patient oxygen can help clear away trapped air.
Unless there are symptoms indicating pneumothorax after the procedure, immediate X-rays aren’t necessary. Follow-up imaging is usually conducted to check for stability or changes after the initial detection of pneumothorax.
The decision to discharge the patient from the hospital after the procedure depends on several factors. This includes the patient’s condition, home situation, accessibility to the hospital, among others. The general observation period after the procedure is usually around 2 hours.
Possible Complications of Percutaneous Lung Lesion Biopsy
The PLLB, also known as Percutaneous Lung Lesion Biopsy, is a procedure where a doctor takes a small sample of lung tissue through a tiny cut on your skin. However, this procedure does have a risk of complications. For instance, you might experience a pneumothorax (when air gets into the space between the lung and the chest wall) or the need for a chest tube (a tube inserted into the chest to remove fluid or air). These complications occur in 45% and 20% patients respectively.
Certain people, like those who are overweight, older, have severe lung problems or have difficulty walking up a flight of stairs, can have a higher risk of complications. Therefore, the doctors might call on specialist consultants who can help, like lung specialists (pulmonologists) or respiratory therapists. There is also a small risk of death after this procedure due to severe bleeding (about 1% cases), air bubbles in the blood vessels (less than 1%), cardiac event, or a severe pneumothorax.
Pneumothorax is one of the most common complications, happening in nearly 25% of patients, but only 0-15% of these cases require a chest tube. The risk of pneumothorax is higher if the area to be biopsied is deep within the lung or small in size, if it isn’t near the lung lining, or for those with emphysema, among other factors. The pain from pneumothorax varies greatly from person to person; some may feel severe chest pain with a small pneumothorax, while others may not have symptoms unless the pneumothorax is more substantial.
If pneumothorax occurs during the biopsy, sometimes, doctors can reinflate the lung. After the procedure, doctors will monitor and if they see any air leakage, they will position you in a way that helps stop the leak. If the leakage continues or if a pneumothorax is large, a tube may be inserted to drain the air.
Hemoptysis (coughing up blood) and pulmonary hemorrhage (bleeding in lungs) can also happen, with pulmonary hemorrhage happening in up to 60% and hemoptysis occuring in around 10% of the PLLB cases. It can be particularly risky for those who take dual antiplatelet medications.
Air embolism, which is an air bubble in your blood vessel, is a rare complication that happens in less than 1% of the cases. If that happens, it may result in symptoms like losing consciousness, stroke-like symptoms, or seizures. To help dissolve the air, you would be positioned in a specific way and given oxygen. If available, a hyperbaric chamber, which helps treat such conditions, may be used.
What Else Should I Know About Percutaneous Lung Lesion Biopsy?
Lung cancer is the leading cause of cancer-related deaths in the United States, according to the Centers for Disease Control. Society’s medical guidelines often recommend that treatment plans for cancer should consider the specifics of the cancer, such as its type and cellular characteristics. While there might be exceptional cases, typically, it’s important to analyze a tissue sample (biopsy) before starting a cure or making treatment decisions to ease symptoms.
It’s critical for health professionals to see their patients as individuals, not just as medical cases. This perspective becomes especially significant when considering a biopsy, which involves taking a small piece of tissue from the body to examine it more closely. Performing a biopsy brings up unique considerations for the patient. For example, some patients might have difficulty staying still long enough for the procedure, or have trouble holding their breath consistently, particularly if the hospital’s CT scan equipment has limitations. Sometimes, professional consultation is necessary before and after the biopsy to manage the patient’s care effectively and prevent any possible complications that could result in a long hospital stay or severe, lasting injury.
Given that skilled radiologists—in medical professionals who specialize in using imaging to diagnose and treat diseases—can usually reach a small target of at least 5 millimeters in diameter and less than 15 millimeters deep, it’s not usually a question of whether a lesion (abnormal tissue) can be biopsied. Instead, doctors and patients should consider the following three questions when deciding on care:
- Has the lesion grown large enough that a biopsy would likely provide a helpful tissue sample? Or should we wait for the lesion to grow further, expecting that we can still likely make a diagnosis before the cancer has a chance to spread?
- If a biopsy is the right decision now, how can the doctor and patient work together to improve the patient’s physical and mental preparedness? This collaboration increases the chances of a safe and successful procedure.
- If the first attempt at a biopsy does not provide enough tissue for analysis, what will be the next step (Plan B)?
