Neck dissection (ND) is a surgery to remove part or all of the lymph nodes in the neck and structures that may be involved with cancer. Types of Neck Dissection include: Selective Neck Dissection, Modified Radical Neck Dissection, and Radical Neck Dissection. The differences are outlined in the table 1. Neck dissection is a complex surgery, and when done by expert surgeons it has very minimal risks. To discuss neck dissection we must first discuss the progression of cancer; cancer grows and advances in steps (Fig. 1 Carcinoma in Situ). It is first contained in the primary site, for example the surface of the tongue (called carcinoma in Situ). Then it penetrates borders and barriers of the surface and is now exposed to the lymphatics and blood vessels. In case of thyroid cancer & squamous cell cancer, it easily passes into the lymphatic vessels and travels to the lymph nodes. In case of sarcomas it preferentially passes through the blood vessels and travels farther distances to the lung, bones, etc…
The underlying philosophy of neck dissection is based on the fact that the head & neck region has a very rich lymphatic system (please refer to the Neck Lymph Node page), once small cancer cells leave the primary site, for example the tongue, they can easily travel through the lymphatic system (Fig. 2 Lymphatic System), and spread into the lymph nodes.
When the number of cells is small, the lymph node will appear the same, but as the numbers increase they become large and have an abnormal shape. From one lymph node they will travel to the surrounding ones and in this way involve many nodes. Travel to other organs usually (for thyroid & squamous cell cancers) happens after spreading to the lymph nodes. Therefore, neck dissection plays an important role in preventing further spread of the cancer.
Neck dissection also needs to be comprehensive and all the nodes in the suspected neck levels need to be removed because there maybe small normal appearing nodes that have a small number of cancer cells in them; this may not be visible on exam, MRI, or PET scans (Fig. 3 Nodes).There have been many years of research to identify where tumors spread in the neck. For example, we know that tumors of the tongue spread to levels 2 & 3 of the neck, while tumors of the nasopharynx tend to spread to the lymph nodes in the level 5 area. With this knowledge, our surgeons will only take out the necessary node compartments, thereby minimizing risk to the patient.
In patients that have cancer in the nodes, surgical removal is one option to treat the cancerous node. Other options include radiation and chemo-radiation. At the Center, the decision as to which type of therapy is made based on the type, degree of aggressiveness, and site of origin of the cancer.
This decision is a complex one and often time is discussed in a multi-disciplinary tumor board.
If the cancer has spread to muscles, blood vessels or nerves in the neck, they will also be removed during the surgery to increase the cure rate; this is called a radical neck dissection. Radical dissection are rarely done, because the chance of tumor involving the vein, nerve or muscle is low and only happens in the rare advanced cases. (Table 1 & Fig. 4 Neck Dissection)
|Table 1||Selective ND||Modified Radical ND||Radical ND|
|Extent||usually 2-3 levels||All levels||All levels|
|Indication||» Aggressive cancer without involvement of nodes (microscopic spread)
» 1-2 small involved nodes in adjacent levels
|» Multiple lymph nodes
» Lymph nodes in multiple levels
» large nodes that are mobile
|» Large lymph nodes that are not mobile
» Involvement of the skin
(See Fig. 1)
|Usually Sub-Mandibular||Modified Schoebinger||Modified Schoebinger|
|Hospital Stay||Outpatient or 1 day stay||2 days||2-3 days, unless reconstruction is needed|
A neck dissection can take anywhere between 1-3 hours, based on the extent of tumor. After the incision is made, the important structures in the neck are identified and very carefully separated from the lymph nodes and preserved. These important structures include the nerves (to the tongue, lip, voice box diaphragm, shoulder, etc…), blood vessels (Carotid Artery, Jugular Vein), muscles, and glands (parotid, submandibular, thyroid & parathyroid).
When the neck dissection is being performed after radiation therapy, it should be ideally done between the 6-8 weeks after the radiation is completed. Before 6 weeks the skin and the tissue is still very swollen and makes the surgery more difficult and healing is poor. After 8 weeks the tissue in the neck start to scar tremendously and increases the risks of surgery.
The risks of a neck dissection include:
- Bleeding, with blood collecting under the skin (hematoma)
- Scar on the neck
- Injury to blood vessels, requiring reconstruction
- Numbness in neck and the area of the lower part of the ear
- Injury to nerves that control the shoulder, muscles to lower lip, tongue, and voicebox
- Chyle leak (injury to the main lymph vessels in the neck that causes an accumulation of lymph in the neck.
After the operation
After the surgery in the hospital, you will be on your oral pain medications for a short period time (roughly 1 week). While in the hospital, you will be seen by your doctor on a daily basis. You may have drains in place. If you have to go home with the drains, the nurses will teach you and your family how to care of them, and you will given clear instructions. The care of these drains is straight forward. You will see your doctor within 1 week after going home from the hospital to check on you and go over the results of your surgery. Often times patients are placed in physical therapy to strengthen their neck and shoulder so that they can resume normal activity in a short time.