What is the lung biopsy procedure and how is it done?

Lung cancer is one of the most common types of cancer in men and women. It is the first cause of death due to cancer. Risks such as smoking, polluted air and asbestos exposure increase the risk of cancer.

No specific preparation is required for the lung biopsy procedure. While fine-needle aspiration biopsy was previously performed, nowadays, a trucut biopsy is preferred, which allows obtaining sufficient material for molecular and genetic examinations. Since a trucut biopsy or core biopsy is taken, it is recommended to discontinue blood thinners such as aspirin. Blood values are checked. The procedure is mostly done under the guidance of computed tomography (CT). The procedure is usually done with a technique called the coaxial (double needle system) technique. With CT, the place to enter the mass and the safe route of the needle are determined. After cleaning the skin, local anesthetic is injected into the area where the needle will pass from under the skin to the pleura.

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Depending on the size and location of the mass, pain relievers and sedative medications can be given intravenously. After the point of entry is determined, the needle step, which allows a thinner needle to pass through what we call the coaxial needle, is controlled by CT and advanced into the mass. After the needle is seen within the mass in the CT, the thin needle in the coaxial needle is removed and the appropriate automatic biopsy needle is inserted, and a tissue sample is obtained from different parts of the mass 3-4 times with this needle. The obtained materials are evaluated by the pathologist during the process and if sufficient material is obtained, the process is terminated. In centers where onside pathology specialists are not available, the material is prepared appropriately and sent to the pathology laboratory. Afterward, first, the automatic biopsy needle and then the coaxial needle are drawn, and the control lung CT is taken and it is checked whether there is air accumulation or bleeding in the pleural space, which we call pneumothorax. Before the coaxial needle is withdrawn, 5-10 ml of the patient's own blood is injected through the needle, and the risk of pneumothorax development can be tried to be reduced by withdrawing the needle. The skin is cleaned in a sterile way and covered with small gauze we call a sponge. If the patient does not develop pneumothorax or is very low, he is kept under observation for 1-2 hours and then sent home without any restrictions in his daily life. If there is moderate and severe pneumothorax, the accumulated air during the procedure is withdrawn with a needle, the air is drawn with a thin catheter, and if these are insufficient, very rarely, surgical drainage is provided with a tube called a chest tube. If a chest tube is needed, the tube is removed with a control chest X-ray after 1 day of hospitalization.

The most important risk of lung biopsy is the collection of air in the pleura, which we call pneumothorax, and respiratory distress associated with it. The risk of pneumothorax is higher in patients with emphysema and in cases where the mass is not located in the pleural (lung membrane or superficial) but is deeply located. In the experienced hands, the risk of pneumothorax is low, and the risk of pneumothorax requiring surgical tube insertion is less than 1%. There may also be bleeding, and bleeding with cough and sputum after the procedure usually disappears within a few hours, sometimes within a few days.

The diagnostic value of biopsies performed with the appropriate technique is around 95%. In cases where there is no pathologist during the procedure, or in some cases, due to taking samples from the part of the mass that does not contain a living tumor, which we call necrosis, or because the area with a live tumor in the mass is very small a definitive diagnosis may not be made.