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Cancer Surgery of the Neck
Richard L. Fabian
The predominant pathology that the surgeon encounters in the neck is abnormal lymph nodes. The scope of this chapter is to focus on malignant cervical lymphadenopathy.
- Cervical lymph nodes are grouped into several levels
- Level 1a, Submental Triangle Nodes between the anterior belly of the digastric muscles
- Level 1b, Submandibular Triangle Nodes within the triangle bordered by the anterior and posterior digastric muscles
- Level 2, Upper Jugular Nodes associated with the internal jugular vein (IJV) from the skull base to the carotid bifurcation; 2a nodes are medial anterior to the ninth cranial nerve (CN IX), and 2b nodes are posterior lateral to CN XI to the skull base.
- Level 3, Middle Jugular Nodes between the carotid bifurcation and omohyoid muscle
- Level 4, Lower Jugular Nodes between the omohyoid muscle and clavicle
- Level 5, Posterior Triangle Nodes between the clavicle, trapezius, and sternocleidomastoid (SCM) muscle
- Level 6, Visceral Compartment Nodes along the anterior midline between the carotid arteries, manubrium, and hyoid
- Level 7, Superior Mediastinum Nodes between the carotid arteries from the manubrium to the innominate vein
Neck dissection is a surgical procedure whereby a surgeon removes lymph nodes from the cervical lymphatic region. Neck dissection is classified as follows:
- Radical neck dissection Resection of nodes in levels 1 through 5, including the SCM, internal jugular vein, submandibular gland, and spinal accessory nerve. Nodes that are not addressed in a radical neck dissection are the facial, intraparotid, retropharyngeal, occipital, postauricular, supraclavicular, and anterior superficial and deep lymph nodes.
- Modified neck dissection Preservation of one or more of the nonlymphatic structures removed in a radical neck dissection
- Selective neck dissection Preservation of one or more of the lymph node groups ordinarily removed in a radical neck dissection. This group is subdivided into a supraomohyoid (levels 1–3), lateral (levels 2–4), posterolateral (levels 2–5, including postauricular and suboccipital nodes), and anterior neck dissection (level 6 nodes).
- Extended neck dissection The inclusion of a region, lymphatic structure, or nodal group in addition to those removed in a radical neck dissection. These structures include lymph nodes in the retropharynx, mediastinum, buccinator and paratracheal space, deep muscles of the neck, sections of the carotid system, nerves such as the hypoglossal, vagus, phrenic, lingual, and facial, and segments of the brachial plexus, as well as portions of the clavicle and hyoid bone.
- Functional neck dissection Serves to remove nodes from levels 1 through 5 without removing any nonlymphatic structure. This operation is technically the most demanding because a complete cervical lymphadenectomy is the oncological intent. Nodes in the high spinal accessory group and level 2a (coffin corner) can easily be missed with subsequent disastrous consequences.
- The shoulder is elevated with a shoulder roll, allowing for full extension of the neck. The occiput rests on a foam-contoured pillow.
- The table is elevated 30 degrees to help reduce operative bleeding.
- A wide-field prep using a head drape and towels allows for the perimeter exposure of the ear lobule, border of the trapezius, clavicle, anterior neck to the contralateral submaxillary triangle, and lower border of the mandible.
- Variables to consider when deciding on the skin incision include the following.
- The two incisions that allow the surgeon to manage most variables are the modified Conley incision and apron flap.
- All preliminary incisions done on a neck (node biopsy) should anticipate a potential neck dissection. This allows the surgeon to place a previous biopsy site incision in line with the incision for the neck dissection.
- The advantages of the modified Conley incision include:
- Excellent exposure and cosmesis
- Trifurcation incision junction is posterior to the great vessels.
- Prevents contraction of the vertical limb by designing a serpiginous incision
- Allows for simultaneous surgery on all primary sites above the thyroid notch as well as bilateral neck dissection
