Invasive Tests, Biopsies & Investigations

1. Cervical Mediastinoscopy

Lymph nodes are found throughout the whole body. They filter out tissue fluids which leak out from capillaries throughout the body. This fluid can contain cancer cells which have broken away from the main cancer, and run in the Lymphatic fluids which are drained into tiny lymphatic channels which ultimately drain into the blood stream. Because of the filtering property of these glands, biopsying them may show cancer cells, and in lung cancer, if cancer cells are found in the lymph glands then this spread will determine that surgery for example may not be the best first option for treatment. Biopsying these glands in the chest requires a general anesthetic. A small incision is made at the bottom of the throat and a telescope is passed into the chest in front of the windpipe. The Lymph glands can be seen and biopsied under direct vision. If it is difficult to biopsy, then it is not proceeded with and a biopsy through the armpit into the chest is performed on another occasion. (Transaxillary biopsy)

2. Left Anterior Mediastinoscopy

When abnormally enlarged Lymph nodes are identified on the CT scan on the left side, they cannot be biopsied through the neck, so small incision is made in the front of the left side of the chest so that one can look directly back into the root of the lung where the nodes sit. This operation of course requires a general anesthetic, and after taking the biopsy and closing the chest, there is usually no need for a chest drain.

Location of lymph nodes biopsied through a left anterior approach.
They lie adjacent to the aorta and pulmonary artery.

3. Transaxillary mediastinal biopsy

In small built people, young people, patients with obstruction to the main vein draining back into the heart from the head and neck ( superior vena cava ) and ones with large thyroid behind the breast bone, it is not possible to do a cervical mediastinoscopy because access is too difficult or dangerous. Therefore the patient is positioned on the side with the arm up on a bar, and a small incision is made in the floor of the armpit, or telescopes are inserted between the ribs in the armpit, to look at the lymph glands in the middle of the chest on the right side. This is slightly more complicated than the approach through the neck because it requires the right lung to be collapsed so one can see the middle of the chest, but it avoids the dangers associated with the neck approach. Lung biopsies as well as pleural biopsies can be done at the same time.

4. Thoracoscopy

Often patients with lung cancer may have fluid visible in the chest sitting around the lung, and pressing on it to some degree. The problem then will be , is it due to an infection in the lung or is it due to cancer being on the lining of the chest wall which seeps fluid. One way of telling is to look into the chest with the telescopes with the video camera attached. The picture is looked at on a television screen at the head of the operating table, and biopsies can be done of suspicious areas. If cancer nodules are identified on the chest wall, then surgery cannot be performed for the cancer because it is not possible to remove totally the lining of the chest wall which sticks onto the ribs leaving tumor behind. Therefore, talcum powder is insufflated into the chest cavity using an atomizer. The talc granules act like sand to an oyster and stimulate a pleurisy which sticks the lung onto the ribs. This means that any fluid which could be formed cannot accumulate, and in fact is not produced any more. The lung remains expanded, and breathing capacity is optimized.