Cancers in the mouth and oropharnyx often spread to the lymph nodes in the neck. There are 600 lymph nodes in the body. Approximately 200 nodes are in the head and neck.
The lymphatic channels are similar to blood vessels, but the channels transport lymph instead of blood. Lymph is a liquid that carries white blood cells throughout the body to fight infection. Lymph can also transport cancer cells to other parts of the body. The lymph nodes act like filters and trap infected material. The infected material can make the nodes enlarge.
If the cancer has spread to a lymph node, the surgeon might advise a surgery called neck dissection.
Neck dissection involves removing the lymph nodes in the neck, and sometimes tissue surrounding the lymph nodes. This prevents the cancer from spreading to other organs.
When a tumor is in the early stages, it stays in the location where it first began to grow. As it grows larger, the tumor is able to travel to the lymph nodes and then to other parts of the body. This is called lymph node metastasis.
The lymph channels spread the cancer to other lymph nodes and distant organs. Removal of the nodes helps prevent metastasis.
During a neck dissection, the surgeon examines the larynx and surrounding areas. Most lymph nodes are arranged in groups. The surgeon will remove the group of lymph nodes that the cancer might spread to next
and any lymph nodes in the neck that are enlarged.
A pathologist will examine the nodes under a microscope to look for cancer. The pathologist will stage the cancer to help determine if the cancer has spread. You might need all of the nodes removed or you may need to have them treated with radiation. If the nodes are not removed or treated, the tumor cells inside them will continue to grow.
Radical Neck Dissection
If the cancer has spread to other parts of the neck, more tissue needs to be removed. The surgeons might remove the muscle, large veins and nerves. If the muscle is removed, the neck will look thinner on one side. The goal is to remove the cancer but save as much tissue as possible.
After surgery, movement of the shoulder will be decreased. Physical therapy can help restore use of the shoulder.
Risks of the Surgery
The greatest risk in a neck dissection is damage to the nerves, muscles, and veins in the neck. Nerve damage can cause numbness (temporary or permanent) in different regions on the neck and create loss of function (temporary or permanent).
The more extensive the neck dissection, the more function the patient is likely to lose. Stooped shoulders, limited ability to lift the arm and limited neck movements are common following radical neck dissection.
Other risks are the same as for all major surgery: potential bleeding, infection, and allergic reaction to anesthesia.