What is the Mediastinoscopy/Mediastinotomy/Chamberlain Procedure?
Mediastinoscopy is also known as cervical mediastinoscopy, or cervical mediastinal exploration (CME). It is a minimally invasive operation performed by a thoracic surgeon. If cancer is present in the lymph nodes of the mediastinum, it means that the cancer has spread outside of the lung itself. The presence of cancer in the mediastinal lymph nodes makes the lung cancer a Stage III. Stage III lung cancers are usually treated with chemotherapy rather than surgery, with a few exceptions.
Why Would I Have a Mediastinoscopy Procedure?
Mediastinoscopy is used to biopsy or remove lymph nodes located in the center of the chest, or to biopsy tissue from a mass in the center of the chest (mediastinal mass.)
How is a Mediastinoscopy Done?
The patient is placed under general anesthesia. The neck is comfortably extended, and the neck and chest are prepped with sterile solution.
A small one and one-half inch incision is made at the base of the neck, just above the breast bone. The muscles in the lower neck are separated, and the trachea (windpipe) is located.
The surgery follows the windpipe down into the chest, where the lymph nodes or mass are located. A mediastinoscope, a small metal tube with a light source inside, is introduced through the skin incision into the center of the chest. Through this tube the biopsies are done. When the biopsy is complete, the mediastinoscope is removed, and the skin and other tissues are closed with absorbable suture material.
What Are the Risks of Mediastinoscopy?
The risk of mediastinoscopy is very low, less than one percent. If there is a problem during surgery, it is related to bleeding from a large blood vessel inside the chest. On a very rare occasion, the chest may have to be opened by sternotomy or thoracotomy to repair a bleeding blood vessel.
What is a Chamberlain Procedure?
The Chamberlain Procedure is also known as an anterior mediastinotomy. The Chamberlain procedure is a minimally invasive operation performed by a thoracic surgeon. A related procedure, known as the Jolly Procedure, is also an anterior mediastinotomy. An extended Chamberlain procedure is called an anterior thoracotomy.
The Chamberlain procedure is used to biopsy lymph nodes in the center of the chest, or to biopsy a mass in the center of the chest. The Chamberlain procedure differs from a cervical mediastinoscopy by the location of the incision, and the location of the lymph nodes or mass to be biopsied.
The Chamberlain procedure is used to biopsy lymph nodes or masses in the aorto-pulmonary window on the left side of the chest, or nodes in the hilar areas of the lung. (In contrast, the cervical mediastinoscopy procedure is used to biopsy nodes or masses to the front or side of the trachea, or windpipe.) The aorto-pulmonary window is the area in the center of the chest bound by the aorta superiorly, and the pulmonary artery inferiorly. This area contains lymph nodes that filter lymph coming from the left lung, especially the left upper lobe. If a lung cancer is present in the left lung, the Chamberlain procedure is useful for staging the cancer determining the extent of spread.) The hilar areas of the lung (the hilum) are the areas of the lung where the pulmonary artery and vein (the blood supply) join the lung.
How Is the Chamberlain Procedure Done?
The Chamberlain procedure is usually done on the left side of the chest, because the aorto-pulmonary window is on the left side. However, the procedure is used for the right side under certain conditions.
The patient is placed under general anesthesia. The skin of the chest is prepped with a sterile solution. A small, two inch incision is made over the second rib where it joins the breast bone (at the Angle of Louis.) The incision is carried down through the pectoralis major muscle (the “pecs”) by spreading the muscle fibers apart. The cartilage of the second rib is located (the costal cartilage) and is removed. The internal mammary artery and vein deep to the cartilage are sometimes tied and cut. The parietal pleura (the inside lining of the chest wall) is then dissected to the side, and the surgery is directed into the center of the chest, between the aorta and the pulmonary artery. Great care is taken not to injure the large blood vessels. Biopsies are taken of the respective abnormal lymph nodes or mass. The incision is then closed, without replacing the cartilage.
Occasionally, the nodes or mass cannot be safely located or biopsied by this technique. Under those circumstances, a decision is made by the surgeon to enlarge the incision slightly, open the parietal pleura, move the lung out of the way, and approach the nodes or mass from inside the pleural space. By opening the pleura and extending the incision, an anterior thoracotomy is created. Because air has been introduced into the area around the lung (the pleural space), a chest tube may be required to remain overnight to drain the air from the chest.
When the nodes or mass have been biopsied, the incision is closed with absorbable suture, and air is evacuated from the chest.
What are the risks? The risk of a Chamberlain procedure is very low. The chief risk is that of opening the pleura, and the requirement for placement of a chest tube (drain.) Although very rare, there is a risk of bleeding from a large blood vessel such as the aorta or pulmonary artery. Such bleeding would require a sternotomy or thoracotomy to stop the bleeding.
Most patients go home the same day as surgery. Most return to work within a few days or a week, and will require pain pills for only a few days. The patient may shower 48 hours after surgery, and should not soak the incision under water in a bath tub or spa for three weeks.